This is also a big win for Windows users since the SSH setup procedure is complicated and error-prone on that platform. Once Windows tools start supporting Smart HTTP, the barrier to start using Git on Windows will be much reduced.
SSH-related issues on Vista consumed, oh, about three days of my life. Using Putty: not bad at all. Tunneling over SSH to do anything useful like Capistrano deploys or Git: owwwwwwwwwww.
Your second statement should be reworded into a fact. It's also a lot easier to convince the people who have to configure the corporate firewall to open up port 80.
It's not just easier for that. I just did a push from a Git checkout on a Linux virtual machine where I'd been doing some debugging. I just had to type in my GitHub password and not set up any ssh keys for a one-off push.