Sure, I'm biased, but Microsoft did a LOT of things right with the 360. It was super easy to post my gamercard on the side of the blog. Here's how to set your up today.
I'm amazed with the richness and integration of data they managed to squeeze into this space that. I changed my avatar online by purchasing a Penny-Arcade pack and it changed in my online gamertag and the Xbox forums as well. I play a game and it shows up in the card. I earn an acheivement... and its in my online profile. Of my non-xbox-dev Friends I have the highest score in Geometry wars... and they see it when they are online and in the game itself. :-)
I know this stuff isn't rocket science, but I continue to be impressed with the "little things" and details that were paid attention to for the Xbox 360.