Mabas9395, thanks for the compliment! Glad it helped! Updated shortcuts list is on there now too.
The individual masks are only editable in LR. There's a good chance ACR will eventually be updated inline with that, but no, they don't then appear in PS as layers.
Grillmouster, you're pretty close. The AutoMask function works like that, protected areas that are not the same colour as you originally started the stroke over. With AutoMask turned off, you are literally brushing the mask wherever you choose, just like masking in Photoshop. You can put masks on top of each other, so in that way, they are similar to layers.
Jann1033 - you have to have Photoshop CS3 10.0.1 for the Edit with extra options to become available, which is why you're not seeing them.
Yes, it saves as you go along in the database/catalog. Makes sure you let it back up regularly, as with any database there's a risk of corruption. You can also write back to the xmp section in the files (sidecar files for raw) which is a useful additional backup. Changes aren't applied to the files until you choose to 'export'.
If you don't already have a Lightroom 1 license, the 2.0 beta will expire within 30 days, but you can ask a license owner for an 'invitation' which will then allow it to run until 31/8.
Mark - soft proofing was on the short list, but got bumped by some of the other features.