HoN has 55 hero's, fast-paced intense arcade action (i love the announcer haha), good graphics, clan support, excellent website + ladder
LoL is very slow, very cartoonish graphics, annoying announcer accent, something like 30 hero's..."edit: oh yeah LoL has Summoner Leveling system, so the more exp you have, the more perks you get (which IMO is very lame)"
i don't know, honestly it just seems like LoL is for children...
i never played WC3, i never played DotA, i never even knew about this "MOBA" style of game before...i'm 27 years old and after about 22 years of gaming from Coleco Vision to WoW/Aion/CoD MW2/Fallen Earth...i can honestly say i really enjoy this genre of game...i don't know what it is...but i love it...it takes alot of skill....
creepwalking, last hitting, denying,...all those small things have a huge impact on late game performance...
anyways....HoN is in closed-beta right now, the invites are currently not working (but i'm sure you can find unused key's easily) so you might be better off to check out LoL...it actually helps people who aren't used to these style of games, and gets them ready for HoN haha
also check out
Bloodline Champions
http://www.bloodlinechampions.com/
that game is gunna pwn