As pretty much the most user-friendly Linux distro out there, I personally think that Linux Mint is the best for new users. As you already mentioned, the people who are so hardcore against anything that isn't open source are probably more tech-savvy, more able to use other distros, but for a typical home user who just wants something more free or more stable than Windows (or OSX), it does make sense for them to go first to the one that's ready to use immediately.
Hell, I *AM* tech savvy, and I'm planning on going with Mint when I eventually ditch Windows (waiting for Steam/L4D2 on Linux). It's a pain in the ass waiting an hour for an OS to install, only to have to go and download a bunch of features that should have been included to begin with. I know Ubuntu isn't quite as bad as, say, Yellow Dog (can't even fucking play Youtube without a ton of work), but as a whole it's still not as complete as most people need.
As for visuals, I don't think any stock install of any Linux distro has looked nice, ever. It's all so bland. For all the work that is put into functionality, a stable core, etc., it seems like there's a significant lack of polish in any of the desktop managers. Most of them look like either a bad OSX rip-off, or a bad XP rip-off. No aesthetic appeal, mostly stuff I could do in photoshop in twenty minutes or less, and poor (seemingly arbitrary) font choices. Mint isn't as bad as some, but even it's guilty.
I'll finish this post later, I just got invited to a game of L4D2.