While I don't think this is the worst photo I've ever seen, I do unfortunately have to say that I don't think it's very good.
First of all, everything else aside, the initial shot could've been done better. The seemingly askew background may work towards the emotion you were trying to convey, but my complaint is more towards the subject, and particularly her hand. Assuming your intent was to show her blowing an "intoxicated" kiss, it's not clear from the position of her lips and cheeks that she's blowing at all, her mouth simply apears to be slightly ajar. Also, this may be more of a subjective point of critique, but in my opinion, her hand is too indistinct and could've used more focus, and most likely placed a little better to convey your message.
Now, I'm sorry but there is little good I can say about the colouring - the most positive thing is that the eyes are, as someone else noted, done with a semi-unique approach that you don't commonly see with eye manipulation; unfortunately, while it is somewhat unique - it looks terrible here, and doesn't fit your image, regardless of the theme. Also, the lips are quite sloppy - you should take the time to do a much more detailed and accurate colouring. Masking is the best way I've found to do this, but whatever method you use, you should zoom in much more tightly and use an appropriate brush (not airbrush in this instance, as you seem to have, unless of course you make the brush size much smaller so you don't see the "splatter" when zoomed out) so that it looks tight and not smudged or sloppy.
Also, I don't know what happened to cause what almost looks like lens flare on your subjects forehead... perhaps you accidentally painted there, I don't know, it just looks bad.
Finally, the colours are far to bright and vivid. I don't know that this image was a good choice for colouring at all, as the darker an image is to start with (shadows etc.) the harder it is to paint colour and still have it look good. That said, you probably still could've gotten away with it had you used much more muted colours, and done a better job painting/masking it on.
I'm sorry that my review has been so negative, but I wouldn't be doing you a favour by sugar coating it - sorry. The idea wasn't bad, just try to develop it better next time - and feel free to keep experimenting, it could turn out better next time. Good luck.
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Below is an example of how you might do the colouring differently. Here's what I did:
First I desaturated the entire image, returning it too B&W.
Next I used the clone tool to fix the smudges around the subjects lips and the spots on the forehead.
Next, I duplicated the layer and masked out everything but the eyes and the lips.
Now, for the actual colouring, as with everything in Photoshop, there are a million and one different ways of doing this, but since I was in a hurry, the one I chose, was to:
A) change the blending mode for the masked layer to "Colour" - again, other options will work, this is just the one I used this time. B) simply grab the paint brush, select a colour and paint over the selected areas (lips one colour, eyes another).
After all that, I played around with what I had - I increased the brightness and contrast, adjusted the hue and saturation of the colouring I'd done.. etc.
Now, in the end - my image still isn't perfect. For one thing, I wouldn't have coloured this image in the first place, and I still don't care for the initial photo itself. Also, because I didn't want to take too much time on this critique, the colouring still could be done better if I'd spent more time on the masking and painting, but you should still at least get an idea for how it can be done differently, and obviously the same approach can be used for colouring other images.
I think Paul's being a bit harsh and exagerating, too. Either that or he hasn't been really looking: there's a lot worse photos out there! :)
The effect is not to my taste, either, but I can see what you are trying to express. I think the image need to be a bit darker, maybe the colours a bit more muted. Definitely try improving the masking for the coloured areas. I'd also sugest darkening the sides, especially the right.
This is quite possibly the worst image I have ever seen. Maybe, just maybe it would work if you had spent a little time masking out the areas you wanted to leave intensely colored. The jagged edges are completely distracting. But the color contrasts are too radical as well. Intoxicated is right. But I think it was the person using Photoshop that was intoxicated.
I like what you have done here. I think that you may have cropped out her hand a little too much. I cannot tell whether or not she is trying to blow a kiss. Is she blowing a kiss? I do like here eyes, the colors are a different approach from what I have seen some do here on eye manipulation. Also, it looks like you smeared the lipstick some, you have to be really careful when you work with selective coloring because any mistake will really stick out. Overall, I like this shot, it is very creative.