Hate to say it, but this is wrong... Unless they very recently gave him an incredible power boost, which wouldn't happen for reasons known to those following Shippuden, then this is incorrect. Asuma was powerful, after all he was a jounin. But in comparison to all the other people who were also alive such as the Akatsuki and all the kages, as well as the fact that each village has multiple jounin with more impressive powers, he can't compete.
Asuma was a highly talented jōnin-level shinobi, having even once been part of the Twelve Guardian Ninja — an elite hand-picked team which served to protect the Land of Fire's daimyō, a role which later earned him a bounty of 35,000,000 ryō.
During the Invasion of Konoha he was able to kill nine Otogakure ninja — who were noted to have been of of chūnin-level or above — with seemingly very little effort. He could also fight evenly with Hidan: a powerful member of Akatsuki while also protecting his team using his skill set. He also established a great record in military prowess — something which many upcoming shinobi greatly admired.
Asuma (was) one of the strongest ninja of his time.
Now asuma may be consider weaker than most. Just Facts...