Not just a witty and disparaging turn of phrase, Captain Obvious is a genuine superhero according to a popular article in the Uncyclopedia.

Together with his trusty sidekick, Readily Apparent Boy, he is frequently called upon to battle supervillains including Professor Subtle and Commander Vague. Professor Subtle remains at large, thanks to Captain Obvious' continuing failure to locate or apprehend him.

Not to be confused with his brother, Captain Oblivious, Captain Obvious' symbol is a large O which stands for Obvious. His alter-ego is widely believed to be journalist Mr. Obvious who inevitably mumbles an excuse and enters a phone booth or public restroom shortly before the emergence of Captain Obvious.

http://uncyclopedia.org/wiki/Captain_obvious