Moved to the Tampa area about a year ago and we love it! I work in downtown Tampa and we are always looking for something fun and new experiences. I'm going to look into one of the suggestions just mentioned on snorkeling in caverns.... Where?
Boating is big, fishing is popular with many community events surrounding contests on biggest catch etc. There are boat clubs in case you don't want to maintain a boat. There are numerous boating areas to beach ones boat and hang out in your own private island or with other boaters.
The beaches are great and any weekend can turn to an adventure visiting different areas. The summers are hot but one can plan around the season with water activities or treat them like one would with ice cold winters up north.
Westchase, Carrolwood, Lutzs, South Tampa all have some really nice pockets depending on your interests. South Tampa is very different to the others mentioned. I'd recommend renting for a year to search the area and determine what you like from food scene, shopping, beaches, water access, etc. City-data has research available on neighborhoods as well. Schools are hard to find in Fl, seems to go more private, but there are pockets of good public schools. Commuting over the bridges are done by all including myself but I wouldn't recommend it.
Places to visit, Treasure Island, Clearwater, St. Pete all of it from downtown to the beaches, Forte Desoto, dog beaches, water parks for families, Orlando for weekend, sooo many restaurants to try. The views everywhere are priceless.