Yes, it seems that they have still not noticed or not fixed all of the very obvious tree generation glitches since Anvil was introduced. A summary of what the problems are:
1) Birch trees are almost non-existant.
2) All oak trees generated are 5 blocks or less tall. No branching trees exist.
3) Pine trees do not generate at all.
4) In swamps swamp trees are only generating in 1 block deep water and are not found on land anywhere.
5) Mushroom Islands do not generate giant mushrooms.
My advice don't play in 1.2.1 until this gets fixed as any new areas in old worlds and entire new worlds will have the above problems.
Hopefully this will get fixed ASAP.
Rollback Post to RevisionRollBack
When no one was looking, the Endermen took forty blocks.
They took 40 blocks. That’s as many as four tens. And that’s horrible.