the photos are not too good... BUT! it's good that you have posted your pictures so that others can comment and in such practice you gain knowledge tru trial and error.
you may however want to diffuse the light more so that they won't turn out to be too harsh... a nice clean background will be preferred too...
i think the pictures are alright, like dejected said, you probably need more light, diffuse the light and you need a clearer background, but i think the dark oof background dont look too bad too.
thanks everyone for your comments and suggestions, will take note all of it..actually this isnt a setup shot w/ proper lights and everything. i just took a snap shot of it when i passed by marina sq for a fashion shoot..
Most of the absolut ads have the bottles illuminated from the top or bottom to make the liquid inside "glow" - it makes for much easier shooting as well since there will be less problem with metering and reflection.