IGN had the chance to chat with Tim Willits of id Software. The two page interview doesn't hold any new information and pretty much comes down to this:

[...] we have QuakeCon coming up, which is August 2nd, 3rd, and 4th right? We're going to be talking about our new game and talking more about Wolfenstein. John's going to talk about some of the handheld stuff that he's been working with on the side.

id Software is showcasing Enemy Territory: Quake Wars at E3 2007. A new trailer of the multiplayer shooter (1:09 min.) can be found at gametrailers.com. id Tech 5 (pictured above) is presented to developers and publishers only -- behind closed doors.

One line from the interview is interesting though:

We also have some other things going on that are pretty secret that we're very busy with as well.

In this context, a recent Croteam (Serious Sam) interview may shed some light on those pretty secret things:

[...] a meeting was held in Zagreb with three main developers from id, Tim Willits, Kevin Cloud and Marty Stratton. They had been decided as leaders for a specific project, a sequel to one of id’s existing games. [...] Although we were close to getting the project, in the end a team from the USA got it.

Gamespot is also running an E3 2007 interview with Steve Nix of id Software. They talk about licensing and the cross platform aspects of id Tech 5.