I've been using
gaim for almost a year now on
Linux. Recently, I tried gaim on windows too. It was interesting to see that gaim used less memory than the
Yahoo messenger or the MSN Messenger whilst providing an interface for both :)
gaim took around 9,932 K, while YPager.exe - the yahoo daemon took 17,964K!
Though it is true that gaim might not be as good as the new yahoo messenger (taking into account that text services, shoutcast, weather etc aren't available when using gaim), its more than what we can ask for, in terms of functioning. Gaim has a lite interface, (at times, the 'sign on' screen doesn't get refreshed soon, but I think this is the gtk issue on win32) and a better set of options for windows (
wingaim plugin). The best part of gaim is perhaps the flexibility in the application with all the plugins we get for it. Adding buddy pounces are a lot useful at times - probably the very nice option that ain't available on other IMs.
But, we're sure to miss out on stealth settings of yahoo when using gaim.
Another significant difference is that gaim is built with a general usage kept in mind, probably. Thats the reason why gaim stands unique and a lot more useful. An example for this - the ability to log into irc with gaim... a complete all in one :)
But surely, there ain't a match for gaim on Linux. Yahoo messenger for linux is full of bugs and irritating piece of software there. So, its gaim for life on Linux!