In an attempt to drive down costs and maximize profits I recently purchased (well started renting) a third server. Right now I'm paying for 3 servers, but will replace the first two servers, my web and mail servers. They will be decommissioned soon and I'll only have one server running.
The third server, will run two servers in a virtualized fashion, thus separating the two tasks of serving webpages and hosting emails. I could run them all from one server (or virtualized environment) but wouldn't like a problem with someone's web based software to allow the attacker to get into my mail system or vice versa.
Today I migrated all my websites (around 30) from MrBurns to Bobo including databases. It was a relatively painless event, it just took some time to set the permissions correctly and double checking that everyone's website was working again.
I Rsynced the websites 2 weeks ago, then again today so that only minimal information needed to be sent over the wire. Then I did a full database dump from MrBurns (the old server) and forwarded that over to bobo and imported it. Things sorta worked out of the box, just had to re-apply permissions in the database.
I'll try and take on mail soon, after that I'll finish moving DNS over either to openDNS or to my servers.