FDQN4FH  Registered user. This application looks to be abandoned. There is a "new beta" on the website, but the current version is largely unchanged since 2006.

Tip: YummySoup will import your Connoisseur recipes quite easily.   
(Version 1.3)

FDQN4FH  This is a very straight forward VOIP client. It has worked well, and is stable on Intel Leopard, and I have used it for hours. Thanks to the developer.

Like Skype and iChat, it allows application-specific selection of the audio in and audio out -- good feature.

No interaction with Address Book. Small complaint.

Requires a SIP account with a VOIP provider.   
(Version 2.01)

FDQN4FH  I just tried it for 20 minutes, and got it straight away. "Got it", and then "bought it". Here's me commenting for a 2nd copy.  
(Version 2.0.2)

FDQN4FH  This is a really awesome program. Not just for the PDF annotations. But also for the speed, and scriptability. (Try scripting in Apple Preview).

Has limitations in selecting (and therefore highlighting) text in columns. I tell myself this is "realistic" behaviour (highlighting separate lines separately). I'm a bit dubious about why highlighting colours should be selected _after_ highlighting, and not before).

I own PDFPen, and have Acrobat Professional at work. PDFPen is awesome for PDF Forms. Acrobat (the Universal version on an Intel machine) is now fast, and has lots of features which need to be rearranged and get out of the way. Both can do highlighting, and annotations, but Skim does it much smoother, and without much fuss/muss. Acrobat can highlight multicolumns properly... but I find the cursor positioning abit odd.

Skim does lack "permanent" annotations, which can be lost if one is careless, which is a negative. Acrobat/PDFPen's annotations tend to be permanent.

Lacks a donate button on the app and website.   
(Version 0.5.1)

FDQN4FH  Good program. Great interface. Works even as a standalone (without the Palm synchronisation). I have 600+ entries: no stability problems. Could be faster on a Macintel: unfortunately no Universal Binary planned.   
(Version 3.32)

FDQN4FH  I've used Yep since for 5 months. I currently have 866 PDFs, running on a fully loaded first gen MacBook Pro.

Yep is quite a Mac-friendly app. However, IMHO is not feature-complete enough to manage large numbers of PDF files. It's very tag based, and yet does not provide enough tools to manipulate and search through those tags. Sorely missing are ways to exclude tags during searches. The interface, while Mac-like, also has deficiencies.

There is a Yahoo Groups based discussion forum. I have sent feature suggestions since I started getting excited about this. Unfortunately while there have been some new releases, name changes, and some feature additions, there is no indication as to whether these feature requests are being considered, or on their way, or an expected time frame. It's cool to have a PDF management system, but frustrating not to know whether it's a good idea to keep using it in expectation that required functionality will be added, and when.

It's cool that the developers have chosen not to use a funky file system, and to write the PDF tags to the individual files (or copies), so that the user can move away from the system as required. While I'm sure they are nice people, and have a nice website, the silence is deafening.

I'd recommend trying this software out cautiously. Unlike other users, I haven't lost any data through normal use. Personally, I'd wait for Leopard to show up before considering paying for Yep 1.2 when it's released. There's NO indication that Apple will add tags to the Finder, but one can only hope. Such tags would IMHO duplicate much of Yep's functionality.   
(Version 1.1.2)

FDQN4FH  Early versions were unstable. But current version is quite stable and awesome. I like the Internet plug-in. And the wmv3 playback. If there is any slight whiff of instability -- then out it'll go.

Some wmv3 files play blurrily, which makes subtitles impossible to read.

The viewing software is free, and fills a useful role where none else could/would: not much to whinge about really. In fact, I would like to say thank you.   
(Version 2.1)