Seems the talk about RIM's official Twitter app was true indeed. It's now officially in beta and if you are lucky enough to have an invite code, you can try it out. Initial reports are that there is no icon caching which causes a little lag in changing screens. But nevertheless, it's another Twitter app to try. It's lacking in some of the features we have all become accustomed to such as, profile settings for mentions. But it also has features that other clients don't. Like integration into the messages list. If you don't have an invite and want to see it in action, Adam Zeis at CrackBerry has uploaded a video of the Official BlackBerry Twitter Client in action. It looks pretty nice aesthetically. I would love to see it running on a touchscreen device. I think the extra screen space would really help out a lot.