It should ship way sooner than Christmas - late summer would be more the target. Stated battery life for our products is based on mid volume 128K MP3, which is a reasonable and fairly common criteria. Obviously you won't get the same battery life if you play 256K Ogg files at full volume the whole time.

We haven't announced the battery life for Pearl yet, however - unofficially - I believe it will be substantially greater than the iPod. The iPod is extremely thin because of its tiny battery, but I think we'll have the better trade off of form factor vs capacity and battery life.

Rob