I like the "Robotic Friends" thing. I may borrow that for my "programming for non-programmers" course. We do a couple of similar exercises (one outside using a grid where one persons walks and another gives instructions, one using a paper gird and written instructions, and one playing
LightBot), but something like this might be a good addition.
I think both the guild and SIGVE things look neat, but neither are things that are high on my personal list. I don't play WoW anymore, and haven't really gotten into Second Life. (Although SL is on my list of "things to look at more closely when I have time", probably right around the same level as Minecraft actually.)
I'm not familiar enough with SL to give an opinion on using for Logic and Program Design. Again, I'd probably go with something like Scratch for that. The main problem I have with using 3D tools for beginners is that it can be very difficult for them to make their own characters/art for their projects. While some students are fine using just "included art", most eventually want a character/object that isn't there. Teaching student to make their own 2d art is significantly easier than 3D art.