Originally Posted by bigbossman
...I'll probably still go with the 13-29 cassette..... :-)
You'll probably want to go with a medium cage rear derailleur for a 13-29. I've heard that a Centaur RD saves you about 1 ounce over Veloce, but that they shift exactly the same (the pre-'07 ones, anyway). You can get a Veloce RD for about $55, vs around $90 for Centaur, and the medium cage Centaurs can be a little tough to locate.
Cheers.