I agree that Batman is overrated sometimes but most of it is due to some of his die hard fans who think he can beat almost anyone with preparation time (Same applies to Constantine fans).
Batman is a part of the Justice League and walks among superhumans almost everyday. What sets him apart from the rest of the Justice League is his incredible prowess in martial arts and his strategic mind. In most adaptations and comics Batman is the one directing most of the JLA around and help them overcome enemies. (Similar to what Captain America did in the Avengers movie).
But now some people have him going up against beings who could be considered gods and winning. People believe he can defeat Superman (Which he can if he plans everything carefully and if Superman doesn't use his powers to their full potential.) and many others simply because he's Batman. So don't blame the character blame some of the diehard Batman fans who believe that Batman can beat anyone.
Ok, before I say anything I would just like to point out that Batman is a total badass. He does everything that he does without super powers and that is definitely something worth noting.
However, part of what makes the JL so great are the super human abilities that they all possess. Batman does not contribute to this at all. He is just an ordinary person. No powers. Nothing special other than an overloaded bank account and technology. He may be smart, but so are the other members of the JL. He may know how to fight, but so do the other members of the JL. He has great leadership skills, but, you guessed it, the other members of the JL have these traits as well. With all of that said, there is nothing that sets him apart from being another average joe. The other members of the JL have the abilities that could save worlds. Batman on the other hand can barely keep a leash on Gotham.
I think that we can all agree that Batman is looked at as a leader in the JL. I do not think he should have this leadership role. My reasoning behind this is that there are heroes of his caliber in other comic book series that do not have the influence that he has. For example, I will use Ironman from the Avengers. Mr. Stark is really smart, wealthy, and knows how to utilize his suit during battle. I think Ironman is a fair equivalent to Batman. Ironman, being as good at what he does with his suit is not one of the leaders of The Avengers. He is more so of a support person. He is reliable to the group and helps wherever help is needed. He uses his abilities to the best that he can to support the group. How is Batman any different from this? He should be more of a support guy. He is just as special as Ironman is and deserves the same amount of leadership responsibility, in my opinion.
Batman is not on my list of favorite comic book heroes. The main reason why I do not like him is because he has no powers; all my favorite comic book characters have powers. It's more fun when you have powers, Batman has only technology. I prefer Superman to Batman.
Batman is a great superhero and is one of my favorites. But when it comes to the argument of his power he is one of the weakest members in the JL. I know that with enough time to prepare or even if he decided to make a preemptive strike, there is no hero or villain that he could not defeat, but it is in that fact is where is where you find his true weakness. Having time to prepare a strategy will not always be an option. Just as the Bat's can make plans on how to take out other super beings, those same super beings can develop plans to get him. Let's look at Superman. All it would take is for the man of still to wait for an opportunity when batman was far away from his lair and after fighting a tough opponent that has now left the tired and weary Batman with most of his gadgets and technology depleted and far from the safe where he keeps his kryptonite, there is no way batman would be able to defeat superman in a 1 on 1 fight. Superman would own him. The fight would be shorter than this paragraph. Once again I state that I am a Batman fan, but do not agree with the level and stature that many fanboys want to post him at.
He is a little overrated but, I actually like Batman because of the diversity of Batman's enemies such as The Joker and Harlequin. So, basically I'm in it for the villains. The joker being my all time favourite comic book villain along with Catwoman. I guess, in all I like the darker, edgier story of the whole Batman universe. If I even make any sense.
The movies don't show the same type of Batman as the comics. In the movies, he's just a martial artist with a big wallet and a lot of fancy gadgets. In the comics, he doesn't have superpowers, but he has mastered every single martial art, and is more intelligent than all the other members of the Justice League. He is a crime-fighting mastermind. His technology and his ruthlessness allow him to compensate for his physical humanity, and that's what keeps him on the level of other superheroes.