Generally, software companies use a beta process precisely because it's impossible for QA to catch all the bugs that would go out in the wild without adding months of testing time. Beta is a win-win situation as it allows die hard customers to test the software and catch more issues before they affect the entire userbase, while giving them a first hand peak at the upcoming functionality.
Some companies only do private beta's precisely for the reason that is cropping up here. Customers not familiar with what beta actually means (not Google's very loose interpretation of it) install it and complain when they find a bug.
As far as I can tell, PBs public release is as stable as, if not more stable than other companies. It is simply not possible for any release to be in the wild and not have any bugs period. At least, it's not possible to do that and keep customers due to an incredibly stagnant release cycle.
If you don't want to participate in a beta or test release, then don't. Or, you could also make the request that they adopt private beta cycles.
As far as user dissatisfaction, user forums represent a very small portion of the user base itself and usually consist of power users, people looking for an answer, people who want to request functionality, and people who want to complain.
This community is one of the more polite, friendly and helpful ones out there. If there was general user dissatisfaction, the forum wouldn't even begin to be close to the atmosphere we have here now. Well, either that or it would be dead quiet.
I'm not going to touch usability. If we have suggestions, then we can suggest them. If we have workarounds, we can share them. I'm pretty sure all the frequent contributors know each others opinions by now, and I think the dead horse has been beaten enough for 15 lifetimes.