Two states (Illinois and Wisconsin) flat out prohibit carrying concealed weapons. It seems impossible to square this with what other states are doing, so "equal protection" looks like it will force a change.
Ten states (Hawaii, California,
I expect it will take some time for the details to get digested. There are a bunch of opinions, and a lot of pages in them.
UPDATE 27 June 2010 17:41: Alabama, not Mississippi is a "may issue" state. Fixed in the post. Thanks to Lweson in the comments for pointing out the error.