Over the weekend I moved from a dedicated server to a virtual hosting environment. It is pretty decadent to have your own dedicated server in a colo, but I was having a difficult time finding the services I wanted. My first attempt with shared UML hosting at rosehosting.com proved to be unusable. The I/O performance was terrible. So I hosting everything myself, including mail, subversion, web site, and development environments.
Since then, I've been slowly off loading to other providers. Amazon's EC2 and an annoying 8:00AM phone call from the billing department at the colo (customer service isn't calling only to threaten your customers) convinced me to ditch dedicated hosting altogether. But EC2 is overkill for hosting my blog, so I am using Plan 96 Xen hosting at Quantact. So far, it has been flawless, and haven't noticed any virtualization slowdowns.
I also moved my Subversion repos to CVSDude. That's been pretty good. They also support Trac and ACLs. Their configuration UI is a bit kludgey, but still better than doing it by hand. Plus I don't have to worry about my server melting down.
I've been using Tuffmail for my email for awhile. Those guys know their shit when it comes to IMAP hosting. I have nothing but good things to say about them. If you are looking for simple email hosting I totally recommend them.