I think HiG said that the Catapult will never see a 2.0 version, but it seems they've been very quiet on all of the small expansions. Many it seems are limited/promotional, so I don't think they will get the 2.0 treatment. But here are my top expansions that will probably never get a re-release. Go ahead and list your favorite expansions that will forever be relegated to Carcassonne history.
1. The Cathars/Siege - Though I think these tiles have a cool mechanism and I have played them on an electronic version of Carcassonne, I think this expansion has gone the way of the dodo.
2. The Tunnel, The Plague, Half & Half, and Little Buildings - These seem to have too much going on to me, but I've never played them, so maybe I'm wrong. However, I don't see them coming to 2.0, and I don't really care one way or the other.
3. The Compass Rose/Windrosen - I like playing with these tiles on the electronic version as well. Too bad they will probably never get an update.
4. Wheel of Fortune - I'm probably the saddest about this one potentially never getting a 2.0 upgrade. The wheel is awesome. Hopefully HiG will see the wisdom of re-releasing this one. I'd be all over it.
5. Castles of Germany - These double-sized tiles look really cool. Never played with these either. I hope they get re-released, but I ain't holding my breath.