Twitter is definitely a favorite of the Mac community and Second Gear is no different. We did create the most popular Twitter client for the iPhone after all.
I've personally been using Twitter for almost two years to chirp about what I'm up to or thinking about, so it seemed obvious to create an official Second Gear account to discuss company-related stuff. Periodically I'll update the account with product updates, contests and maybe some coupon codes.
We also have a separate Twitter account for PocketTweets that we have been using to keep users up-to-date on updates to our favorite iPhone client. And just for fun, if you're interested in following me personally, you can too.