I'm just learning on our new Canon T1i, so constructive criticism is welcome!
I'm not the best at offering criticism (it's a character flaw). I'll say a few things though. Take them with a HUGE grain of salt. Often in life you get what you pay for, and internet comments are obviously free. Thanks for taking the plunge and posting though. I love viewing the images posted by members of this forum. While not all of them do something for me personally, that's okay. I appreciate the fact that people feel comfortable posting *whatever*. It makes for a nice environment.
I'm not sure what level of criticism you desire, as I'm not sure what exactly your goals were with the image. This doesn't reflect poorly on you, it's just I can't read your mind.
For me personally, there isn't enough contrast between the colors present in the main elements and the color of the background. The cork tends to blend in with the table. The white balance seems a bit too red, so maybe just tweaking it a bit towards the blue side would be be enough to create some contrast between the color of the cork and the color of the table. Alternatively, putting the wine bottle and cork on something else (Black marble maybe? A blue table? A red table? A white table? Anything not tan/brown?) might help to make the bottle and cork really stand out. I do like the details of this table though, the little spots are kind of nice.
The base of the wine glass in the top is a bit distracting for me. I would have either composed to exclude it altogether or perhaps introduced the wine glass into the composition to play a more central role. Possibly the entire wine glass (with wine in it, though that would mean you would have to step back a bit and include more of the bottle as well which might detract from the impact) or just the base and stem placed above the cork with the body of the glass excluded (maintaining your current composition with the addition of the lower part of the wine glass to strengthen the message--wine, drinking, yummy). Glassware can be tricky though--if it isn't pristinely clean the spots/smudges tend to really stand out in photographs.
The final comment I would make is that for still-lifes such as this, sometimes playing with the lighting can have fairly dramatic results. This is somewhat trial-and-error (at least until you get comfortable with it). But having a focused light source behind, in front, or to the side (doesn't have to be a purchased photography light, even a simple house lamp will do) will cast shadows that can sometimes add impact to an image like this. It doesn't always work out, but sometimes the interplay of shadow and light can add to an image.
I'm just some random guy on the internet. Don't take any of this as gospel. If YOU are happy with the image, that is all that really matters.