I'm not shy of admitting I'm a major fan of Picasa. OK, so it might not be the most fully-featured piece of software on the planet, but there really isn't an end-to-end solution like it, especially given the price (free, for both the client and the service).
The client is fairly slick in the way it picks up on new photos without intervention. It's also fast - even on my 5 year-old PC, I can scroll through photo albums smoothly, and it indexes new photos really quickly, up to roughly 10 per second or so.
It's also simple enough to use that my wife now uses nothing else for browsing out photos (which is growing larger by the day). Heck, it's simple enough to use that she figured out how to order prints by herself, which is definitely something.
The old storage limit (100MB?) was a bit restricting, but the 1GB limit is fine if you're only uploading stuff reduced to 1600x1200 or so. That should be large enough for browsing on just about any machine and detailed enough that friends and family can order 6x4" prints if they want, and you should be able to fit thousands of photos inside the limit at that size.
Try doing that with the likes of flickr, where their free account is limited to 200 photos visible, and more annoyingly, 3 sets (i.e. albums). Lame! That's why I use flickr for mucking about with and post albums for family and friends to picasaweb.
The downside? You have to sign up with Google. They probably know who you are already anyway...
