I have been reading comments on this post on Meebo's blog. Although there are lots of comments about how primitive meebo still is but I can see many people actually like it. I'm one of those.
I have IM accounts for MSN, Yahoo and Gmail talk. After many years of using them I know what I actually need from the interface. I don't need fancy UI, ads, tons of functionality and complicated settings....not even smileys, I hate them. In communication text counts most everything else is minor.
For meebo to really take off I think they need to integrate it with other popular stuff such as Ajax first page and browser. There are a lot of these so called Ajax Homepage now, Techcrunch has reported. If users really like you that will be the first page they see and meebo deserves a little corner in that first/homepage.
Currently IE7 beta doesn't support meebo. Firefox is the best outlet for meebo to enhance their functionality if an extension is built for firefox. Imagine meebo could open up on a sidebar with login credentials memorised by the password manager of firefox, alerting me within the browser when someone buzz me or send me a nudge (currently meebo doesn't do that yet). That'll be great.