Google's Picasa software and the Picasa Web Albums have been brought much closer together. Now it's much easier to load photos, and a new sync feature will automatically update your web album when you change your photos on your computer.
There's also a new name tags feature which has the ability to automatucally group photos containing similar faces - so this can let you tag many photos in no time at all.
More refinements include an Explore page showing recent photos from all over the world, and the ability to email photos directly to your album - great for sending from a phone. New creative tools allow movie and collage creation, and retouching and text controls. Check out http://googlephotos.blogspot.com/ for the latest on this.