After gracing the cover of Forbes Magazine, Sean Parker of Napster and Facebook fame has finally given in and joined the microblogging social network, Twitter. After apologizing to Mark Zuckerberg, Parker, the Facebook Founding President, tweets that his decision was made under the influence of his friend Scooter Braun.

Parker’s new Twitter bio, which includes references to Napster, Plaxo, Facebook, Causes & Airtime and the Founders Fund, confirms our earlier speculation that Parker and Napster co-founder Sean Fanning are partnering up once again to launch a new startup called Airtime.

Currently, Parker’s Verified Account (which means he’s been planning this for quite some time) has less than 500 followers. We predict he’ll get to 200K today.

To add to the list, follow him here @sparker.

Screen shot 2011 10 03 at 3.00.15 PM 520x185 Sean Parkers First Tweet: Sorry Zuck