I've lived in Mazatlán for 4 years, and after visiting other cities, wouldn't live anywhere else, although I do head for higher elevation during the hot summer months. I'd be happy to answer any questions, but in the spirit of full disclosure, I do volunteer work for the tourist bureau, so I "might" be a little prejudiced. The yahoo forum group Mazinfo is an excellent source of information, as is the Mazatlán section of TripAdvisor. Some other sources are:
mazatlanmylife.com
mazatlanmycity.com
pacificpearl.com
maz-amor.com
