I switched over to Tweetdeck a while ago… I use to use Gwibber on my laptop/desktop machines and Peep on my Android phone but recently switched…
HTC Peep was ok but honestly it use to wind me up when it wouldn’t update when the storage was quite low. No warning either. Gwibber was great but I found it slow when adding lots of columns. I tend to have a column for all the people I’m following (home) one for replies (@replies) and finally one for Private messages (d msgs). On top of that I have searches for events and the such things. Tweetdeck handles these pretty much in its stride, but Gwibber use to do odd things.
I think it might have something to do with being connected to Twitter x2, Identi.ca, Facebook and other services.
The one thing I do miss from Tweetdeck is the ability to connect to a identica and status.net server. Instead there’s accounts for Facebook (which actually works very well) and Google Buzz. Honestly I’d switch out Buzz for status.net anyday.
I don’t know how the news Twitter might buy Tweetdeck will effect everything but it looks like status.net and even the open microblogging standard isn’t coming any time soon. I may switch back one day, specially if Gwibber 3.0 is as good as it could be.