While we’ve known a bit about T-Mobile’s 3G rollout plans for a while, it has all come from hearsay and posters taped to windows.

T-Mobile finally came out and announced their plans this morning with a good ol’ fashion press release: 27 markets by the end of 2008, with 21 of those swimmin’ in the 3G waves by mid-October. It’s all pretty close to what we’ve been hearing whispers of for weeks, just with a couple of markets slipping under different launch windows.

Check after the jump for a breakdown of all the cities.

Markets currently with T-Mobile 3G (13):

• Austin
• Baltimore
• Boston
• Dallas
• Houston
• Las Vegas
• Miami
• Minneapolis
• New York/New Jersey/Long Island
• Phoenix
• Portland
• San Antonio
• San Diego

Markets getting T-Mobile 3G by mid-October (8):

• Atlanta
• Chicago
• Los Angeles
• Orlando
• Philadelphia
• Sacramento
• San Francisco
• Seattle

Markets getting T-Mobile 3G by the end of 2008 (6):

• Birmingham
• Denver
• Detroit
• Kansas City
• Memphis
• Tampa