Gamespot and IGN have updated with impressions of San Fierro:
"While some stats you can improve by the kind of self-schooling described above, others will require a more-formal approach. As a result, plan on getting some schooling during your time in GTA: San Andreas. Of the schools you'll find in the game, driving school is arguably the most important one you'll attend. The driving school will teach CJ new techniques that can be used in the game or enhance his existing driving skills. As you'd expect, better driving skills will improve his overall control over a vehicle, eventually enabling him to do things like make sharp turns at high speed, or quicker-than-usual stops. One thing to note is that four-wheeled vehicles in San Andreas feature in-air control, meaning you can adjust the pitch and roll of your vehicle in mid-air much like you could on motorcycles in Vice City, though not nearly as quickly. Gaining this skill may turn out to be pretty handy if you happen to take an accidental jump off a canyon, which could actually happen. In addition to in-air control, you'll be able to learn controlled stops, how to control your car when a tire blows out, and the perfect barrel roll."
http://www.gamespot.com/ps2/action/gta4/preview_6110172.html
http://ps2.ign.com/articles/556/556064p1.html