Without exception, the drivers enjoy Monaco because it is such a dangerous and difficult circuit, which requires precision to achieve a good lap time. Mistakes, even small ones, are punished with a quick trip to the scene of the accident.
Both McLaren and Redbull had made huge errors in the race. When Glock retired with a suspension failure, McLaren somehow misunderstood where he had stopped on track and assumed that it was a safety car situation. It was not, but McLaren immediately brought in Button, which cost him the race lead and the chance for an easier win. Button fought back into second place but still needed a third stop to satisfy the "use both tire compounds rule". Button rejoined in third place and demonstrated the benefit of fresh tires as he rapidly caught Alonso. It was some impressive driving.
Due a miscommunication, the Redbull mechanics mounted hard prime tires instead of soft option tires on Vettel's car in his first stop. Since the tire compound rule was satisfied, Redbull boldly switched to a one stop strategy, but it would require Vettel to eke out 61 laps from the prime tire which was only expected to last 45 laps! This set up a fantastic three way fight for the win between Vettel on old tires, Alonso on slightly fresher tires, and Button with the newest tires.
The race's final major incident, involving Alguersuari and Petrov, red flagged the race which allowed everyone to change tires under the suspended conditions. The equal tires nullified Button's advantage and deprived us of an epic finish.
Hamilton had a torrid weekend. When Perez crashed in the third qualifying session, it was red flagged while the track crew reposition the barrier he had displaced. At this point Hamilton had not set a competitive time yet. When the session restarted, he managed to qualify seventh, only to have the time deleted because he cut the chicane. Using his Q2 time, he qualified ninth.
Hamilton's frustration showed on Sunday as he barged around the track, incurring two penalties for causing avoidable accidents. The saddest one involved Maldonado, who was having an excellent race and looked set to score good points for Williams.
Barrichello scored Williams' first points of the season which demonstrates how a good driver can carry a car around this track, and why the drivers love the circuit so much. I doubt that the Williams improved that much since the previous race.
Tires, KERS, and DRS all contributed in some way to more passing than is usually seen in Monaco, a notoriously difficult track on which to pass. And yet the passing still required obvious skill and daring. The new rules worked very well in Monaco.