Interestingly enough Bluegayle, I find the reverse to be true. I've also recently realised that a big factor is where you start.
I have started most of my characters in Dun Morogh, Orgrimmar or Mulgore. There, the ore is pretty abundant, and much of it can be found outside of caves. However, I found the Human starting area to have somewhat less plentiful veins about, and the Night Elves can't even start mining until they reach Auberdine!
On my server, however, mining is much more worthwhile than herbalism at low levels (at least until you get into the level 20-30 area), since copper ore gets ~50 silver for a stack of 10 ores, while Peacebloom & Silverleaf get less than 10 silver for a stack of 20. Of course, AH prices will vary from server to server, so herbalism may end up being worth it for some, and not worthwhile for others. Just make sure you compare prices!