Chambers USA has released their 2012 rankings of the top law firms and attorneys which places each notable firm and attorney into Band 1 and Band 2. It also designates a star individual for each practice area. I have copied the tax lawyer rankings and the corporate/commercial law firm rankings. The complete rankings for all practice areas can be found by clicking here.
* Full disclosure, I am an associate with Chun, Kerr, Dodd, Beaman, and Wong LLLP.