Everywhere else I can sign in with my hotmail e-mail except for MSN. Anyone else have this problem? =\ Help is much appreciated, thanks.

Common problem with the new version, I had to go back to 6.x to get in..... Then I deleted the friggin' app from my computer and went back to Adium.

I tried Adium and I hate it.
I'll try and download the lower version of MSN.

the 6 version doesn't work either...

I really don't like any version of MSN Messenger for Mac because they're shi*. I prefer the Windows version but it's not worth the effort to turn on VMWare every single time so now I use Adium. It's one of the best ones out there.

What's VMWare?

It's like a virtual OS that can run simultaneously with Leopard. Although, you need an Intel processor.
VMware: Virtualization via Hypervisor, Virtual Machine & Server Consolidation - VMware
I use it for Windows XP which is pretty good since I only have 1GB of RAM so I loaded XP with 256MB.
Here's a screenshot.

Also, a neat feature about this is that you can copy files between OS's.
There is also a similar product to this (and commercial) and that is Parallels but VMWare is much better!
If you want a free software like this, you can try Virtual Box (or try the VMWare 30 day trial).