Quake Live, the upcoming free in-browser version of Quake, is sending out beta invitations to the service. Users are directed to beta.quakelive.com
This is a grand new experiment in gameplay. Instead of charging users a monthly access fee, id Software is teaming with IGA Worldwide to add advertising and sponsorships to the game to make money. Early reviews of the game are a thumbs up, and it looks to be a one way train to zero productivity at work. We’re trying to track down video of the beta environment.
The trailer for Quake Live is here.

An interesting study was performed by Tim Hong of EmSense where they measure the physical reactions of gamers to different games. Among the information gathered was the different levels of engagement based on pacing, tutorials and cutscenes.