Well i go for Thesis WordPress Theme , Headway WordPress Theme and Catalyst WordPress Theme as one of the most SEO optimized WordPress Theme
Believe me bro a theme really doesn't matter a lot! I've seen blogs standing first in the Google Search Page with the basic theme 'Twenty Ten'. I've also seen many other blogs not using thesis and still ranking high!
Woothemes are great themes which have user friendly menu and you can also move your theme settings from one site to another (if you using same theme ) via themes framework.
There is no "best" theme for SEO. Read any SEO book, or search engine guide and you will never see any of them mention that some themes are better than others. This is a marketing trick that theme makers use to impress, and attract noobs. There is no truth to it.
You can use any theme, Just install Yoast plugin. It all all the best feature of a SEO. and not to forget any good SEO Book
There are only 2 frameworks ("themes") I'd consider respectable for SEO: (1) Thesis (the best!) and (2) Genesis (by StudioPress). I had some spare cash, so I bought both a couple months back. I've done several experiments on both and I can tell you that Thesis is #1... for SEO, speed, typography, etc. I'll be migrating my main site to the Thesis-based one in a couple of weeks, say end of March. I'll also blog about my experience with some premium themes - Thesis, StudioPress, Catalyst, Pagelines, etc. Feel free to check out my blog in a couple of weeks. I suggest you try Thesis first - they offer a 30-day trial period, so there is very little risk on your part. The support forums at DIYThemes are second to none!
Install all-in-one-seo plugin because it works regardless of what theme you use. Having this plugin means you do not need a "SEO friendly" theme.
The best Wordpress theme for SEO is the Heatmap theme. I rank on Page 1 with this theme. Hybrid theme is also excellent but looks a bit uninspiring. Another great SEO theme is the Education theme. http://YourCNATrainingGuide.com ranks on Page 1 for this using CNA Training as the keyword.