OK, so these releases are a bit confusing, so let me explain:
DBD::SQLite is the active release of the driver, tracking the current release of sqlite (currently 3.0.4)
DBD::SQLite2 is the old release of the driver, tracking sqlite 2.x (currently 2.8.15), and I won't be updating it very much at all. Everything is renamed, including all the internal C functions, so that you can definitely load both DBD::SQLite and DBD::SQLite2 in the same program and not have conflicts. The only significant changes since 0.31 are the update to sqlite 2.8.15, and the addition of the busy_timeout API from DBD::SQLite-1.0.
And yes, before the bikeshed painter brigade comes out, I know the "2" on the end makes the second one look more up to date. There are multiple reasons I chose this scheme.
Available on CPAN as soon as local CPAN mirrors update.