The official WP7 MSN Messenger app has a ridiculous 1.5 stars in Marketplace. It’s really a shame because if this was a robust app then it would be the strength of the platform (tie in all forms of chat, and various IM clients like Facebook, add some video support and bam). Anyway, for now it appears to fail hard. The complaints range from an inability to login, frequent crashes, inability to sign in if you’re already logged in on a PC, etc. So it’s actually worse than the Windows Mobile app. So why put up with it? Why not just load Messenger in browser. Just direct your phone to mim.live.com/wlm and you can sign in from there. Obviously, there’s background support since IE has background support. You can sign in to multiple accounts and it’s pretty easy to have multiple conversations at once – there’s actually a decent interface for that. The one problem is that the app doesn’t ping/autorefresh when something happens so you need to sit there like a fool and refresh. Well maybe it does but I’m totally impatient and in testing it I never waited beyond 15 seconds cause I expect IM to be real time. So it’s not perfect at all but considering how bad the native app is, it may be an alternative until they fix it.