HOFMAN  This seems pretty unnecessary. Using the version string in the URL is not even the proper way to pass the version. The version should be set in the appcast, which is much more reliable and precise. It is not even guaranteed that Sparkle will support getting the version from the URL in the feature, my guess is that it won't.  
(Version 1.2)

HOFMAN  Skim allows you to save a copy of the PDF with the notes embedded inside the PDF, compatible with other programs, using the Export action.  
(Version 1.3.1)

HOFMAN  There's nothing Skim can do about this, because you lose the notes when you save from another program. Skim has no way to change the way Preview or Acrobat saves data, that should be obvious. Remember, you also /see/ a PDF without (Skim) notes in Preview, so you should also expect to save it without notes when you do a save from Preview. That's /your/ fault, not Skim's. It's simple: save Skim data with Skim, and save Preview data with Preview. If you mix that up, you may expect problems.  
(Version 1.3.1)

HOFMAN  Supporting Tiger would mean NO new development for anybody, it only holds back improvements for everybody else (which is now almost everybody). So supporting Tiger would mean NO difference for Tiger users and a HUGE difference for everybody else. And you can still use version 1.2.7 on Tiger.  
(Version 1.3.1)

HOFMAN  My guess is that you're talking about saving a PDF with Skim notes with other applications that do not know about those notes, such as Preview or Acrobat. This is indeed not a bug but expected behavior. When you edit and save data with a particular application, than you will save only the data that application knows about, and you should expect to lose any data that application does not recognize. This is true for any type of data and any kind of application.  
(Version 1.2.7)

HOFMAN  Both are issues with the system, and are outside the control of Skim. The first is a shortcoming of Apple's PDFKit, the main engine behind Skim (and Preview). The second is about the system print services, which handles the print job based on your settings. My guess is that you also don't choose an appropriate paper size for your business cards, which almost certainly don't have your default paper size.  
(Version 1.2.4)

HOFMAN  And to be clear, this was fixed in 3.5.1, http://www.mozilla.org/security/known-vulnerabilities/firefox35.html#firefox3.5.1.  
(Version 3.5.1)

HOFMAN  It may also mean that some people have suggested Xcode from the page of the other apps.

It seems that "other people suggest" can either mean that someone has suggested the other app from this page, or that they've suggested this app from the other apps page. Makes no sense to me, but that's the only way I can explain the strict symmetry between the number of 'suggestions' from one app to the other and the other way around. Just follow any of the links and compare for the suggestions on that page. Works for any review on MU.  
(Version 3.1.3)

HOFMAN  BibDesk does index the contents of attached files (such as PDFs) only once. In fact, it even caches the index between launches. Note that indexing a large number of attached files can take a while, and for that matter BibDesk can even divide the long indexing process over several launch sessions. Probably what you think is a re-indexing is in fact a continuation of the indexing process, or an integrity check that BibDesk always does automatically when it loads a cached index.  
(Version 1.3.21)

HOFMAN  Saying that it's designed for scientific papers is not the same as saying that this is its only use, but the latter is what the MU summary implies. The description on the Skim website also clearly qualifies the statement. So either please add a qualification to the summary or, better, remove the "for scientific papers" entirely. Also, I can propose a change for everything on the listings on MU except for this summary. Why not?  
(Version 1.2.3)

HOFMAN  I can't get this to work with FireFox, it simply does not appear in the popup for PDFin the Applications preferences and it also does not appear in the Plugins list in the Add-Ons. Of course I installed it in /Library/Internet Plug-Ins, and I even changed the owner to root. So what else do I need to do to make this work?  
(Version 2.3)

HOFMAN  Many reasons, here are just a few. It's windows-only. The free version is almost certainly not sufficient for useful integration in a PDF viewer. Apple's PDFKit does not allow sufficient control over its internals to add any OCR "layer".  
(Version 1.2)

HOFMAN  You shouldn't mess with the inside of the app, if not just because it won't stick on updates. The classic FF 2.x theme is available as a theme from Mozilla's site, as well as many other themes users may like even more.  
(Version 3.0.5)

HOFMAN  The question is not "which version", but rather "which app". There are AFAIK 4 different mac apps for Gimp with varying characteristics in integration in the Mac OS. The one at http://gimp-app.sourceforge.net has an experimental version that is the only native version I know of. But I have never tested it.   
(Version 2.6.3)

HOFMAN  What made you think this one does not launch X11? The abstract clearly mentions that Apple's X11 is required, and there's no mention that it runs without it. There is only one version of Gimp for MacOSX I know of that does not require X11, and that's not this one.   
(Version 2.6.3)

HOFMAN  Acceptable (free) OCR is not possible for free and within the contraints of Apple's PDFKit, unfortunately. For column selections, use the Option key, read the FAQ on the wiki for more details. This is also behavior dictaed by Aple's PDFKit, so if you'd want this to improve more than what Skim is capable of, you should ask Apple.   
(Version 1.1.13)

HOFMAN  For 1, simply choose "Use Current view Settings as Default" from the PDF menu. For 2, you can block-select by holding the Option key (this is standard selection behavior in Cocoa apps). Also read the FAQ on the Skim wiki for more tips with regards to this.  
(Version 1.1.13)

HOFMAN  Why don't the Description and Requirement sections agree? One says it's for Intel and PPC, while the other says it's for Intel only. The fact is, the Description has it right. MU, please fix the Requirement.  
(Version Update 2)

HOFMAN  The concept is really nice. But unfortunately the implementation is very buggy. There are some critical bugs, and it has a huge chance to lead to namespace clashes, due to its implementation of many categories on Cocoa objects. Due to the nature of this framework, as a simple drop-in utility, this is pretty serious. Moreover the localizations are missing.

Anyone should be aware this is a *beta* version. MU should have noted this, probably this version should not have been listed at all.

I strongly advice developers not to use this version. And if you do, be aware that you *must* fix its bugs and be very well aware of the namespace problems.  
(Version 1.5b1)