USB microphones are not just more convenient than the regular analog headsets, they also give better audio quality and generally require no special audio drivers.

Digital Arts compared popular USB mics like Rode Podcaster, Samson G-Track, Blue Snowball, Marshall MXL.006 USB with a professional quality microphone and concludes:

"If you don’t require pristine audio and prefer the convenience of a plug-and-play solution, either the Samson G-Track or MXL USB.006 is a good option, with the G-Track getting the more-enthusiastic nod thanks to its more-flexible recording and output options.

If you demand a microphone that sounds like those found in a professional recording studio, none of these USB microphones is what you’re after – instead, get a "real" microphone, plug it into a USB or FireWire interface, and learn to use it. " Link.