I've already sent out a message to those I contact frequently, but for the rest of you, my email address has changed from email@example.com to firstname.lastname@example.org.
I have decided to migrate away from Gmail for a variety of reasons. I figured I'd use my domain so that I have flexibility in my provider choice. For example, if I decide to change my mail provider I don't have to get a new address. So this change should be permanent.
Now, being a tinkerer, I figured I'd set up a mail system for myself that retains the features I like from Gmail while doing away with the downsides of using Gmail. My final system is complicated, but effective. And it was a fun four days setting it up! (No, that wasn't sarcasm. This is the kind of thing I enjoy.)
My MTA is Postfix, running on mail.chrishowie.com. It accepts mail for me and delivers mail from me. The standard security features are in place: SPF/blacklist checking and no unauthenticated relaying. I also established SPF records for my domain. I do not have a spam filter, but I might set up SpamAssassin later if I actually start seeing spam in my inbox; no spam has made it past the sender blacklist check yet.
For downloading mail, I set up Courier as a POP3 server. The observant will note that this would nullify one of the most useful aspects of Gmail: access to your email from anywhere. Once you download from a POP3 server and delete, your mail is gone from the server and lives in your mail client.
That's where the rest of the rig comes into play. On my home LAN server I have a multi-piece system that provides me with this anywhere-access. I have a getmail4 cron job that fetches mail from my POP3 server, as well as from my Gmail account (so people can still reach me using my Gmail address), and some of my other mail accounts, and delivers the mail to my maildir using Dovecot's delivery agent. From there, the agent processes my sieve rules, sorting my mail into various folders. (It's like your favorite mail program's "filters" only it runs on my server instead of my mail clients, so the configuration is centralized.)
For reading all this mail, I run Dovecot, an IMAP server. All my mail clients fetch mail from this server, and since it is IMAP, changes to messages (like moving a message between folders, or adding tags, or whatever) are actually pushed back to the server. So I can use several mail clients at once and they all have a consistent view of my mailbox.
The only major piece I have yet to set up is an LDAP server for centralization of my address book. The rest has been working quite well. I can use Thunderbird at home, or my mobile phone's email client when I'm out of the house. No limiting or inconvenient web interfaces required.