Have you tried ubertwitter? There is the beta which is the newest. I use it and I think that its fast and doesn't eat too much memory. You can get it here. Just visit this link from your berry and you'll see the download link in the post!
I haven't noticed any performance issues with UberTwitter or Seesmic. Seesmic is the one I like the more of the two, but it's inability to remember my username/password after a restart of the phone is annoying.
Ubertwitter is great but if you can get Socialscope i would recommend that. Its great for facebook and twitter combined and blows ubertwitter away in my opinion. And alot of ppl say it drains the battery but mine updates every 15 mins and no problmes.
I use Thetweetgenius and have been for almost a year now. It is a costly price now of 7.99 i believe back when I got it, I payed 3.99 but when they have new updates I get a email with a ota link no paying again for it. It is a very nice paid twitter app if you have it you will never get rid of it.
For fb and twitter status updates and friends' status check, I recommend vodafone update. It works on every network, not only for vodafone. It is I guess by far the most useful application I tried. Vodafone Update
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I've tried Ubertwitter, agree its the best as well, but it seems that it is slow, constantly downloading stuff and images.
Also, noticed that when I uninstalled it the folders on my SD card did not get removed. I used FileScout to delete and fully cleanup these folders and was surprised that it took 1 hour to fully delete the Ubertwitter folder. What could it of been downloading and storing on my SD card? The must of been lots for images or soming.
Posted from my CrackBerry at wapforums.crackberry.com
If you're interested in speed, then try Seesmic for Twitter updates. If you want both Twitter and Facebook, then try Snaptu. These are the fastest Twitter/Facebook clients I've used.
