So, now the cat is out of the bag, so to speak.
Tiger ships with SQLite 3.1.3 + a couple of tweaks. Specifically, the SQLite3 on Tiger supports locking on network filesystems, including AFP and Samba.
Tiger uses SQLite3 in a number of roles. It is a backing store to Core Data -- the new object persistence & object graph management solution in Tiger -- and is also used by a number of applications on the system to provide better searching/indexing capabilities and as a primary data store.
Personally, I would like to extend a very hearty thank you to Richard and all SQLite contributors. Working with SQLite has been a joy and Tiger benefits greatly from the addition of this wonderful tool!
b.bum