Strangely, as of this post (about three hours after Reuters' report), there have been no tweets on this event within 100 miles of Tehran in the last several hours. That includes tweets in Persian, Farsi, and Arabic, after Breaking Tweets translated these messages.
But the world is reacting:
@travelphoto (San Jose, Calif.): Iran launched their first satellite. Probably trying to find out what Obama types on his Blackberry.
@andycal (Wolverhampton, England): Why is the Iran satellite described as 'home made'. Gives the impression it was built in a shed.
@wsm1, a quantum physicist working at NASA per his bio, offered the following:
@wsm1 (Calif.): so the NORAD TLEs confirm that Iran did launch a satellite. http://www.planet4589.org/latest.html