By the look of it I think special issue means that bakuman made the front page and that it got featured in centerpage as well (getting front and center is pretty rare),the center color page illustated the poll results.
Also,completely unrelated:even though I dropped blood-c I can't but be hyped about the movie after reading the synopsis and watching the trailer,I'm wondering if you checked those out.
Oh no it was an answer to the question "which fictional manga would you like to become real" poll.Ohba's shown us glimps out of most of them in the manga but appart from otter 11 that got a 1 shot there's nothing else to base your vote on
More bakuman news,detailed poll results have come in,Otter 11 got 7th place.
There's a bunch of manga that havn't heard of,I'll list the ones you know:
18th:Kiyoshi Knights (Fukuda's manga)
16th:Saint Visual Girls Academy (briefly mentioned in the anime,Miho's first role)
9th: Superhero Legends (the manga written bu Mashiro's uncle)
7th: Otter 11
5th: Detective Trap
4th: Money and Inteligence
My personal favorites came in 3rd and 6th.
Sorry,no Hideout Door,but there might be another Aoki Manga you havn't heard about yet in there.