Stores get shipments in every day. From what I am hearing, RIM and ATT are making sure that they are ready to meet the strong demand. They have learned from the 8700 launch. Sometimes it is better to not commit to anything until all the channels are stocked.
Also, it is not uncommon that stores will NOT have pricing and availability until they actually receive the devices. This was true for the 8800.
The press release will be unveiled soon. Wouldn't be surprised if we see it this week