I have the same problem, and I've tried applying manually downloaded patch, as well as reinstalling and patching after. None of that worked.
Interestingly enough, I tried patching to 1.21b after trying to patch to the newest, and it didn't work either. Nor did 1.21a, but every patch before that worked. However, they've [1.21a -> 1.22] worked in the past (but I've since reinstalled XP Pro). I also tried installing some of the possibly missing dependancies -- such as Visual C++, which was missing the last time. It didn't help either.
My conclusion is that either this is the same problem as before (as in the last patch), but I merely didn't remember to go through all the steps to fix it, or that there's something else wrong with the updater.
I managed to solve my problem by patching my WC3 running on computer running Linux using Wine and copying all the needed DLLs, executables and MPQs. This means that if there's a missing dependancy, Wine has it (probably).
bnupdate.log has the following content:
Blizzard BNUpdate v2.63 compiled on Apr 10 2003
Log created at 2:03 pm on 03/20/2009
ERROR: unknown command on line 3 of file patch.cmd in archive D:\games\war3\War3Patches_TFT_123a_enUS.exe,Patch_War3x.mpq
RESULT: Patch failed
Earlier it also had something about worldedit.exe, but unfortunately I don't have that log anymore. I didn't have the version of worldedit.exe, like some others reported, so that wasn't the problem.