DotA is oD&D. It's the original, it has some warts, but they're charming warts that add to the gameplay.
Let's say Demigod is, I dunno, The Fantasy Trip. It's silly, it's bizarre, and you get the sense that the creators maybe didn't play the original the same way the original designers did. But it's not bad. It has its fans, and probably always will.
League of Legends is, let's say, Warhammer Fantasy Roleplay. It's its own thing, it plays differently, and you either love it or hate it. I've yet to meet somebody who has a totally neutral opinion of it.
HoN is like Basic D&D, or the Rules Cyclopedia. It was supposed to just be a better chassis to play roughly the same game, but it ended up being its own thing. By the end of its lifespan (Immortals rules, anyone?) it ended up being so much of its own thing that comparing it to what it started out as didn't even really make sense. It could also be Advanced D&D, the comparison is close enough for me. The point is, they're comparable games that don't quite play the same way, but have the same basic concepts.
DotA 2 is oD&D. Again. Without changing anything. It's not even Swords and Wizardry. It's not a "Here's the game again, but with clearer rules and a couple of nifty changes I think you'll like that only affect the game in minor ways!" No, it's like they went and re-released oD&D while pretending it was something new, and wanted some money for it.
And everybody's hailing it like it's the greatest thing ever. Like it's some messiah to save us from the other games.
Let me link you some videos, real quick, and you can see what I mean.
Thanks, Valve. Why is everybody getting so excited again?