I tried most of them last night (*hic) and here's my tasting notes (all on the rocks):
Bulleit: just a hint of sweet with a strong spicyness. Different from what I had expected but I like it a lot! (I also love the bottle. Cork top is classy)
Mt Gay: Very very light flavor; just a hint of a sweet molasses smell and it disperses on ice. Wish it was a bit stronger...
Tanqueray: My first gin. Very smooth, but kinda stuck me as similar to licking an evergreen. It grew on me as I drank, though.
1800: Very light flavor, kinda dissapointed. Was hoping for a little more agave oomph. Very sippable, though.
Svedka: Superior to Smirnoff, for what it's worth. Definitely worth the buck over Smirnoff. This one'll be a fine mixer, but just isn't quite up to sippin' standards.