MP,

You should be aware of everything.

Are your Servers names actually changing? What about share folder names? Instance names? DNS names / pointers? Permissions?

If you're going to be on different machines, quite likely a lot of that is changing. You need to make a list of every SSIS / DTS package, every job and every program (within your power) that points to old machine names and shares. Those will have to be updated during the move. Also, URL links that might change (SSRS, etc.).

You'll need to verify you can, at need, remote into your database servers (test Remote Desktop). That's assuming you're still administering the servers as usual, of course. Also, you'll want to make sure you get all your jobs/packages/FTP links moved to begin with. And File Shares. Don't forget those.

You'll want to make sure everyone's off the system during your move, then backup & detach your database so no one can log back in and change data while you're moving. When we did a side-by-side upgrade to new boxes, we simply copied the files and logs of all the user databases and re-attached them on the new server. Notice I said "Copy", not "Move". This is important, because if the re-attach fails and corrupts your files, you'll still want the originals around for a while. We kept ours for a couple of weeks, just to make sure.

Keep all backups for a couple of weeks after the move for "CYA" purposes. Additionally, the first 2-3 days, you might want to utilize differential backups to cover yourself. Make sure the old server, while offline, is still available to move back to for at least a week (maybe two). Again, this is CYA. Then go through the old server files (once the move is complete) and make sure you've gotten EVERYTHING off it, or at least archived to another location (tape/CD/etc.).

Check everything 3 times. Even if you've checked it before, check it again. Believe it or not, you will miss something no matter how hard you try. But the more comprehensive your original move sheet is, the less you will miss and the faster your move will go.