Lots of people get stumped by the BDB 4.8 dependency. It is starting to be really hard to get in modern distros. Even if we were to go to some magic append-only wallet format we'll have to support it for foreseeable time for backwards compatibility.
I think a script that fetches BDB 4.8, configures and builds it statically would be useful. Then change the bitcoin autoconf to automatically pick it up (and set include/library path accordingly) if it was fetched this way.
Note: I am not proposing to add BDB to the git repository like we did with leveldb. Just to make building against the "holy version" easier.