We have been to Sardinia for 12 days two weeks ago and it WAS just amazing. If you are looking for photographic paradise this must be one your options. We made 1100km during 12 days and every day we've seen something different. If you want to shoot beaches and sea then Sardinia must be your number one. You will find best and cleanest beaches over there, certainly better than any beach in Spain and continental Italy. People are lovely and I was not afraid to keep my Pentax *istDS + lenses + my bag with photo equipment on beach whilst we did snorkel 100 meters or more from our things.
We have been to south of Sardinia (very close to Cagliari in village called Pula) with plenty of beaches close to our B&B. My favourite has to be Chia, you will find a lot of beaches over there. With car it took us only 20 minutes to get there. I would certainly recommend trip to St. Pietro island. You have to drive there for hour and half but it's absolutely worth it. If you love snokerling you will find real gem over there. I will post pictures from over there, it was just wonderful (well for my wife it was quite scary, you know a LOT of fishes and other underwater life).
That's it for now. I will upload my pictures to my Picassa gallery here.
Ok, that's it for now. I will post a lot of pictures from Sardinia.