Unless you have a lot of content of the same quality level, don’t show works in progress. Especially not front and center. The implication is that it’s the best you’ve done yet and that you’re desperate for content. It makes me think that you don’t think any of your other work is as good as this unfinished piece, and that you don’t have time enough to finish it before putting it on your portfolio. It comes off as unconfident and desperate, and that’s really not something you want to telegraph to a potential employer. 🙂
Don’t get me wrong, I think having an area for works in progress is just fine, but they should be separate from a portfolio and not placed front and center. It’s also fine (and often cool) to see work in progress images leading up to the final piece. But your portfolio shouldn’t be focused on unfinished crap if you can help it.
The way I see it is this: Professionals’ portfolios contain a healthy amount of finished work that’s of a consistent quality level. The finished work is the focus. They don’t put works in progress in the middle of the rest of their finished work.