Agreed. Its quite a bit different than Slugging [npr.org] that is/was popular in some cities. These newer programs have apps for ride matching, rating systems, and at least informally set fees. Its a regulation dodge more than anything else.
Definitely - and they're not turnout out to be so successful at dodging the legislation after all. There are other companies that do "real" carpooling though, such as e.g. Avego. They've been getting a lot of attention during the BART strike now, with them offering to actually fly commuters to work by helicopter ( http://bartstrike.com/?page_id=1073 ).