Yet, recently surfing the net, I found another: http://www.slideroll.com. That's free with some limiations (say, you could upload 100 photos at most), of course, you could pay $35.40 per year (or $7.50 bimonthly) to go pro.
SlideRoll provide a webpage for each users to show off their slideshows, no matter whether you've paid for it or not. Frankly speaking, it's easy to make a slideshow with that.
- sign up an account;
- upload your photos from your PC or import from Flickr;
- do some creations to the photos;
- preview and publish;
Besides, you will get the HTML code for that slideshow, if you want to show it off on your blog, Myspace, etc.