Generally tailoring has been one of the better crafting professions to have gold making wise due to their ability to craft high end sellable cloth that was on a cooldown. Currently, however, Dreamcloth is BoP meaning that at this time tailors don't have this ability. Thus while historically it has been one of the better crafting professions to have from a gold making standpoint the general concensus now is that since Cataclysm it has been one of the poorer crafting professions to pick.
1) Easy to level
2) Anyone can gather the materials needed for this profession - just kill mobs that drop cloth.
3) If you play on an RP server there are quite a few recipes that might sell well due to aesthetic reasons
4) You can make bags and there is always a market for bags.
1) No sellable cloth cooldown is really hurting this professions gold making potential at this point.
2) The Dreamcloth cooldown limits the amount of high end goods you can make.
3) Not a huge market for most items
My advice on tailoring: I am still rather bullish on tailoring in the REAL long term (later on in Cataclysm and perhaps next expansion). I think that there is a good chance that at some point they will regain their ability to sell their high end cloth that is on a cooldown and when this happens I expect the profitability of tailoring to rise quite a bit. Right now though, most people seem to be having better luck with leatherworking and blacksmithing. Tailoring definitely has some items that sell but it has definitely lost some of its profitability since Cataclysm came out.
Recipes of Note:
1) Netherweave and Frostweave bags are selling for a profit on many servers.
2) Epic Spellthreads are often profitable.
3) If you are on a Roleplaying realm look into items that look good and/or different. Things like masks, tuxedo jackets, dresses can often be sold for a profit.
Recent Power Word: Gold posts related to Tailoring (auto-generated).
The Power Word: Gold Guide Free is Copyright © 2011 Jim Younkin. Guide contributors include Bangkok Bill and fluxdada.