We stayed at the Sheraton Towers in May. You can't beat it for the location, and the food is relatively good. We ate outside of the hotel most days/nights (DH had a conference and I tagged along, brought my little sister too). Our room was nice sized and very Scandinavian- decor was very modern and sleek. Being near the train station was awesome for me and my sister- we took the Tunnelbana everywhere, and DH took the commuter trains out to his conferences everyday. I have to say Stockholm is one of the most expensive cities I've ever been to, and I thought the Sheraton was a rather good deal.

Make sure to get some softserve while you're there, it's really, really good... ^