I've been to the Bahamas in November and January and the water was warm enough for me in November but a little too cold for swimming in January.

No one can tell you exactly what the weather will be like for you or whether YOU will find the water warm enough.

If the averages are 70-75 then *I* would find it a little too cold for extensive swimming (maybe a 5minute dip!).
I regularly swim in a pool where the temp is usually 78-80F and the heater broke recently so I found out my limit. Below 75F was too cold for me.

Oops, I forgot to add you might want to consider renting a wet suit for your trip for a little extra warmth.

The trouble with "averages" (especially when it comes to temperature) is that they don't tell the whole story. For instance you could have one day with a high of 100 and with a a low of 60 which averages out to a daily temerature of 75 (a comfortable temperature) but in truth neither of those days is particularly comfortable - one is too hot and one is too cold. While this is over simplified my point is you need more information to make an informed decision as to whether or not the temperature during December will be "right for you". Also, you don't say when in December you are going and there could be a significant difference in temperature when you compare early December with late December.

You can reasearch what the actual temperatures were on Exuma (or any other destination for that matter) for every day during the last 10 years for any given period at www.wunderground.com. Using the Travel & Activities dropdownmenu select "Trip Planner". Enter the airport code for your destination (for Exuma it's GGT) and your planned dates of travel. You'll then be directed to all types of charts and data showing actual daily highs, lows, wind speeds, etc. Clicking further down through the material will give you temperature reading that were taken every 15 or 20 minutes during each day. After reading the material you'll be a weather expert for Exuma and you'll know more than most locals.

A quick look at the charts shows temprature ranges in December from the low 60's to low 80's (which goes to my point about averages).

If you go, do as sassy suggests - bring a wetsuit if you plan on swimming a lot. Personally, I'd go somewhere further south in December.

RoamsAround, I think most weather sites average the HIGHS and LOWS separately so it's not quite as extreme but I get your point.

Sounds like SavTrav is a little less savvy about temperatures and wants to know what 70-75 will feel like to them.

I know there are many people that are happy to swim in water that's around 60-70F . The Cap Cod beaches are filled with them all summer long!

sassy - I get where you are comming from.

I've been to Cape Cod in summer and the water was way to cold for me to spend much time in the water. Went to Martha's Vineyard a year ago and didn't go in the water once.

Obviously, I'm not the one to tell anybody if water temps in the 70's would be all right for swimming.