SHK747  no problems at all.

mac pro, imac, umbp ..  
(Version 5.4.2)

IAMDORIAN  One wonders if this is in response to the recent faux pas updating to OS X 10.5.7. That update caused by Airport card to completely loose connection to my Apple Express AIrport box. I'll try the update and see if this fixes that problem. ::: crossing fingers:::  
(Version 5.4.2)

FIREMIN  Mmmh. Don't know if this release is the problem, as I haven't had to log in to my Airport Base Station for some time. BUT.... Now, I can't log into it. Airport Utility 5.4.1 says it can't find any Apple airport devices which is truly interseting because I am connected to the internet via the same Airport that the Utility says it can't find!!   
(Version 5.4.1)

MBP GKB  5.4.1/7.4.1 Airport update

I've been using the Time Capsule as my primary network. I extended my network with an Airport extreme (version prior to the latest). It's been working on 5.3.2 and has been solid as a rock. When the update came out, I was excited. I downloaded it and installed it and WOW my internet connection was screaming fast! It lasted just long enough for the back up to start on the Time capsule. The TC started failing backups, my connection to the net turned into the slowest thing since my 56k modem days. I started out by believing that Apple could do no wrong and fussed at my ISP. Well, I started hunting around and it seems others are having issues with this update. I'm noticing connection drops, the email client won't log in, I'm actually trying to connect to my neighbors ISP just to download the older version (it's still on your mac in the library directory, so if you can't find it or can't connect, look there) I back loaded to the 5.3.2/7.3.2 version and what do you know, it works great again. Solid as a rock. A week went by and It was working well. I thought again it might have been the ISP and updated it again (because my Airports were screaming at me 'Update available!') It was super fast for about 3 minutes. I was excited again for 3 minutes .. then it was back in the commode again. I'm now back on 5.3.2/7.3.2 and am happy to stay there until apple fixes this patch. Three words for you my friends ... DON'T DO IT!!!!'  
(Version 5.4.1)

TDU  I have the same issues as previous posters. My wireless connection had been bulletproof up until installing this update. In my case I didn't even mean to install it was the worst part. Airport Utility asked if I wanted to update it when I had it open, and I wasn't reading the dialogs carefully enough and hit ok by mistake. I have regretted it ever since. My connection CONSTANTLY drops. If I leave the computer idle for more than 1/2 hour, I end up having to reset my base station just to get it to show up. It costs me a ton of time each workday.

This update has been a DISASTER for me. And obviously from the reviews, I am not alone. I normally only leave comments and not a star rating, but if anything deserves a one star ratings it's this software. Definitely proceed with caution if you plan on using this.  
(Version 5.4.1)

MISCHIVO  This update has bugs in it. Whereas my network was A-Okay with the previous version, it now has a major issue: it periodically loses connection every dozen minutes or so. It does this by either disconnecting me from my network (even though my network remains in the pull down list) or by simply losing connection to the Internet even if the network connection remains strong. In each case, turning off airport and turning it back on fixes the problem.   
(Version 5.4.1)

RIP0FF  FUBAR! it worked on my PPC G4 but the base station network can't be seen by my Intel MacBook (Other networks in my neighborhood show up). What's going on ?  
(Version 5.4.1)

M85  After I upgraded to 5.3.2 it took two hours worth of reboots and unplugs to get my base station to see my airport express again. I won't touch 5.4.1 or any other AAU update until I see a bunch of trouble-free reviews.

GLTA  
(Version 5.4.1)

SHK747  after updating to "this" (Version 5.4.1 (541.9) my 5ghz xtreme is unreadable.

whats going on ?

all soft on latest standart,10.5.6  
(Version 5.4.1)

JEREMYK  I just installed the airport 5.3.2 update and now my network is screwed up. beware.  
(Version 5.3.2)