There's doubt Silva is #1 because not every person is a rational, unbiased non-fanboy. Fedor could get KO'd by Shinya Aoki and to some, he'd still be the GOAT. 
Wandy's run was more impressive that Fedor's, and more impressive than Andy's so far.
"But why do people disregard Rogerio WALKING THROUGH Henderson?"
Wasn't Dan supposedly ill for that fight or something? I also wouldn't say he walked through Dan, although that was how I used to remember it too. A minute into the fight Dan had already gotten a takedown and busted Rogerio up a bit. They brawled a bit, Rogerio put him down (not sure if it was a slip or knockdown), Dan got back up, clinching, Dan took Rog down again. Rog threw up some subs, Dan escaped. 7 minutes in, it had been a fairly competitive fight. After the latest break, Dan was badly gassed, Rog boxed him up a bit, stuffed a takedown, got on top and got the armbar.
Also, despite Dan getting a takedown and having a few minutes of lay and pray, Anderson beat him in less time than Rogerio -- or anyone else -- did. He and Dan also likely weighed the same in the ring, while Rog almost certainly had 10-15lb on Dan.
"Vitor came in off 1 year layoff, fight at 195, surgery"
I like the notion that Vitor having fought at 195 somehow makes Anderson's destruction of him somehow less. Explain that for me, please.
"Griffin came in off loss"
Like Coleman and Hunt? At least Griffin's stint at #1 (in a higher weightclass) had only ended 8 months prior to fighting Anderson, compared to 4 years before fighting Fedor like Coleman's did.
"Hendo came in off loss"
Like Tim Sylvia? At least Henderson wasn't finished in his loss.
"Franklin went 2-0 got rematch where as Nog had to go 5-0"
Yeah, Nog "had to go 5-0" because Fedor was too busy fighting the killers of the division like Fujita, Goodridge, Nagata, Coleman, Ogawa, and Randleman. Meanwhile, Mark Coleman went 2-1 -- the wins being over guys entirely irrelevant in the division -- and got a rematch with Fedor.