I've installed 'Pidgin protocols plugin for Conversation and Contacts', which includes MSN (Haze), and I'm very happy with it, at least with the MSN integration. I've not tried the Facebook one, because I do not want all that contacts in my Contacts app, so I'm waiting for the possibility not to add them (hope it will come...).

if you want to use MSN, go for Pidgin plugin for conv./contacts, it's the best.