My family and I use
www.fotki.com. We pay like $30/year to use it, but we seriously LOVE it and just paid for years 3-6, lol. It was easy to use for my family that didn't know alot about computers, and we all just upload all our photos/layouts to the one account (we just share the username/password) and can download the hies files from there.
We started it because we do family vacations every year and there are literally THOUSANDS of photos - so it was the easiest way to get ahold of the photos we wanted.
Now we have pictures up for all sorts of stuff, and each "family" within our family (ie, each of my sisters' families, my parents, and my brother) each have a folder to just upload random photos to.
Oh, and also...forgot to mention this because I haven't used the feature yet...Fotki has some pretty good prices for printing as well. They do all sorts of sizes, including 8x8 and 12x12, but the services are only available to Premium (ie paying) members.

I need to try them out soon, I just never think of it.
ETA their prices: 9 cents for 4x6, $1.90 for 8x8, $3.90 for 12x12...there are TONS of other sizes as well.