Wow, I'm surprised at the reactions to level scaling, particularly as the lack of level scaling has completely killed so many MMOs for me.
I gave up Bioware's SWTOR MMO because you couldn't even do half of the content in that game without completely out-leveing the content as I progressed through my character's story - and that's really frustrating for a completionist type of gamer. I spent most of my time fighting MOBs that were so far below my level that there was absolutely no challenge or fun to be had in fighting them.
I started losing interest in Skyrim after I started one and two-shotting everything, including dragons. Again, due to a lack of level scaling.
On the other hand, I actually started playing Diablo 3 again because (among many other needed changes), monsters in that game now scale to the players level - meaning it's impossible to out-level the content and just mow through everything. Not having to worry about leveling faster than the content around me is a dream come true.
You can still have challenges ranging from easy to nearly impossible with level scaling. What you don't have is content becoming obsolete because you out-level it.
