Oh, I would never hail it as the best to date.
Iron Man comes close cause it's pretty loving awesome. Batman maybe, though to be honest I'd rather go with the Tim Burton films (specifically Batman Returns) as the greatest super hero movie ever rather than the Nolan films. I know a lot of Dark Knight fanboys are going to eat me up (or out, rawr) over that, and they are very well made films, but they just don't feel like Batman Batman. They're Batman, for sure, but it's that ultra-real that I'm not too huge a fan of.
And sure, people are gonna say that that made it 'betterer' because it was more 'irl', but that's not where Batman started. To me, Batman Returns glorified the Batman mythos onscreen and made the characters the center of the action (much like Dark Knight did) but added that suspension of disbelief. That nonspeaking character that was Gotham City played a pivotal role in the film and not only added atmosphere, but it also added depth. It felt that the pages were onscreen and captivated the audience with breathtaking scenery as well as deep, Batman-ness stories.
Dark Knight was in Chicago. Bland, clean, everyday Chicago. Batman feels more like Commando in a Batsuit rather than Super Hero.
Where Dark Knight may have shined in its character driven stories, Returns did that and added an element of otherworldly quality that makes Batman Batman. And then obviously Schumacher took a huge stuff all over Batman and so two movies later Begins and Dark Knight were fresh and fantastic new films that really put Batman back on the market.
Each film is fantastic, but in my opinion Returns wins the day.