James,
I'm catching up with this thread so I'm sorry if you've already discussed the details of this pictures. What equipment did you use (camera, lighting, location). The pose and model's expression are excellent. What does your Post Processing work flow look like?
One major beef with the finished image is the use of soft focus or similar effect. I mean, this is not 1989 and you are not shooting for a hair metal band. You probably spent thousands of dollars on camera gear to achieve the sharpest image possible. I just think you do yourself a disservice by using this technique on top of the really great capture.
Other nits I have with the post processing: I would spend some time and clean-up the sclera (whites of the eyes), whiten the teeth, and recreate the key light reflection in the model's right eye. I'd also hit those lips with the dodge tool to brighten the reflection. Here's a before/after comparison with the changes I've described. They are totally natural looking and not extreme, which I think is important.
Also, if your original image does not contain the far right bits of hair that are cut off in the linked image, then I would consider a tighter crop. Either of the ones indicated in red below would work.
Finally, unless you intend for your images to bee seen on multiple pages when printed don't size your image so big that people have to scroll. I mean, who has 2200 vertical pixels on which to view the linked image. This one is only 600 pixels high and allows the viewer to get a much better feel for the overall composition.
Seriously good work here that blows most of what you have on your website away. You should consider replacing most of your portrait stuff with studio shots like this one.
Good luck!