I live in Central Florida, don't do off roading, but went for 4x4. Here's why:
1) I've got 9 acres- mixed pasture and woods. The 4x4 comes in handy for moving a 16' tandem trailer around the property when cleaning up. (Lots of soft sand.) It is also great for tensioning trees/large limbs when cutting them. Not to mention pulling out shrubs...
2) We get some serious rain downpours in Florida. Many of the roads don't drain fast enough and end up with an inch or more of water on them during heavy downpours. 4x4 feels much safer to me then 4x2 under these conditions. It seems like the chance of hydro-planing is reduced since the front wheels are actually being driven.
3) Resale value- I tend to keep a vehicle for 6-8 years. My experience has been that the added purchase cost for 4x4 is almost completely recovered when the vehicle is sold. While there is certainly more potential cost for maintenance costs with the 4x4, I haven't experienced it. (Aside from changing the differential, an extended warranty would cover these within its limits though.)
The Tundra is my third truck. The first one (1977 Dodge Club Cab) was 4x2. The second one (2001 Dodge Dakota Quad Cab) was 4x4.
I like having the 4x4 available, even if it rarely gets used. A couple of years ago, I was going from one part of the county I live in to another; the map showed a direct road that would save about 20 minutes. About 10 miles down the road, it turned into a dirt road. a mile or so later, it was a path thru the woods (too narow to turn around and go back). I would have never made it thru there if the Dakota wasn't 4x4. (No, I know how to read a map and the map gave no indication that this was actually just a path thru the forest...)
Spending or not spending the extra for 4x4 is like everything in life- make the best compromise you can based on your situation. If you need to reduce the cost as much as possible, skip it. If you can afford it, go for it and you'll get all or most of it back in the end.