Y'know, at times it's really hard keeping up with all this social stuff on the internet. This is because of the separated nature of the way this crap works. However, after some trial and error, I think I finally found a way that works for me.
Posting to Facebook and Twitter
For this I'm using AIM. I went all ICQ-happy for a while, and I still use it, but the AIM client is more clean and posts status updates to Facebook and Twitter easily. I'm happy with the way it works, save for one thing - it doesn't notify you (or at least not well enough) when you get an @reply in Twitter.
Getting notified of Twitter @replies
I'm using echofon (formerly TwitterFox) for this. The way it works is great. It's a tiny little icon at bottom right of the Firefox browser. If you have an @reply, a number shows next to the icon. For two @replies, it shows a 2. Simple and easy. And I can reply right from within the browser which is even better.
The best part is that I've finally been able to dump twhirl. That client is old, hasn't been updated in forever and isn't worth using, so I was happy to switch to echofon.
The bar thing on the bottom of my site is Meebo Bar. I don't know if I'll be keeping it or not. I dig it because it has a WordPress plugin, so there's no theme modding required. It also supports custom menus and you can even add in your own custom icons to it as well. I like the fact I can have my YouTube and Twitter stuff directly in the bar instead of having to shove it in a sidebar.
My only real issue with it is that it's a chunky piece of code and slows down my site a bit. I don't like that. But we'll see.
I'm waiting for Windows Live Mail Wave 4 to come out so I can try it. The current Wave 3 is good but not good enough. It's supposed to be released soon, but until then I'm still using TB 2. I gave it a new look by using OxyBird, and it makes the client look so much better. Much more modernized. Very clean.
Wave 4 is supposed to bring in new features that I can actually use, such as tagging and the ribbon interface which I actually like.
TB 2 unfortunately is probably the last TB I'll ever use, because 3 was such a disappointment. Actually, I'm sugar-coating that. TB 3 is a piece of crap. Unstable, crash-prone, ridiculous interface.. the list goes on and on. If this is the best Mozilla can do, then no wonder more and more people stick with webmail.