read all the surfer threads on pages 1 2 and 3. and as batman is conscerned, this guy has no superpowers and defeats people way more powerful on a regualr basis. why do you think when ever someone makes a "who can beat so-in-so. . ." someone always puts "batman with preptime lol jk omfg etc" theyre making fun of his overatedness.
I think Batman comes across as being underestimated because there's alot of haters always trying to put the man down. Another reason might be that Batman actually has to work for his victories, unlike so many other characters that just rely on there powers.
As always fanboys will overrate the character, but that could be said of any character who actually has fanboys, including all the ones that have been named in this thread.
Anyway I think Judge Dredd and Hellboy are often underated. Judge Dredd as far as ability and story goes, and Hellboy only powerwise.