Yes he is trying to legitimize himself as a replacement but I also think that fight was much bigger for Bisping personally than most realize.
When he fought Wanderlei he wilted in the biggest fight (until that point) of his life and was fortunate to go the distance against a legend that had certainly lost a step or two by that point. I imagine that loss has really stuck with him as he didn't perform to his ability that night.
Another older legend of the sport he fought was Hendo, nuff said.
The Anderson fight was another shot at a superstar of MMA, who old or not nearly everyone considers "The Goat" of the MW division.
Bisping's experiences in the former two fights kept him from being seen as an elite fighter by most fans and possibly, himself.
He needed that win as validation, it may have been ugly and his opponent may have been a shell of his former self but he was able to succeed where he previously faltered and probably feels like a weight he has carried for a very long time has been lifted off his shoulders.
How quick people forget that everyone was saying Bispings career was past its prime before the Silva fight too 
tryonmytoupee -Me tooBobSherob - For some reason I want bisping to take this one. Kind of a reward for effort thing. The dude has been fighting his arse off for years and finally has his shot.Was talking about this with a friend tonight.
Good luck to him
Bisping used to annoy the shit out of me. Now I'd love to see him win the title, then happily retire.
The guy has fought through a lot, and from everything I hear is amazing with his fans.
Fight. Promotion.
ranier wolfcastle -I think Anderson went over the top when he celebrated winning that 3rd round.
judonoob -Bone Tissa - How dare Bisping try to promote his title fight. What a dick.
S Dubaya -It's marketing and self-promotion. A win with Silva helps cement this being an exciting fight. Rockhold sure is looking like a smug twat though. Zero likability. Hope that bisping gets it tonight, so we have an entertaining and enjoyable individual to follow.perfectsoldier - Like he beat the prime killer Anderson of old is starting to get annoying.I picked that up too. He did mention it a few too many times. The fact that it could have gone either way and Anderson is a shell of his former self should make Bisping a little more humble about that win.
I know part of it is as a salesman trying to legitimise his title shot for more last minute buys. But anyone with half a brain knows that the win was questionable, and a prime Silva would've given him the Forrest Griffin treatment.
Looking forward to seeing Rockhold mow this guy down again.
People are quick to discount Bisping's win over Silva with excuses how it wasn't "prime goat Silva", but I don't remember them doing the same for any of Silva's opponents when he won.
TX_432 - I thought Anderson was still a killer and his 2 losses to Chris were flukes? Which is it????
what
perfectsoldier - Like he beat the prime killer Anderson of old is starting to get annoying.
I know part of it is as a salesman trying to legitimise his title shot for more last minute buys. But anyone with half a brain knows that the win was questionable, and a prime Silva would've given him the Forrest Griffin treatment.
Looking forward to seeing Rockhold mow this guy down again.
Next thing you know Bisping is going to be claiming he beat Luke Rockhold. The nerve of this guy.
Looking forward to seeing Weidman mow this guy down.
perfectsoldier - Like he beat the prime killer Anderson of old is starting to get annoying.lol
I know part of it is as a salesman trying to legitimise his title shot for more last minute buys. But anyone with half a brain knows that the win was questionable, and a prime Silva would've given him the Forrest Griffin treatment.
Looking forward to seeing Rockhold mow this guy down again.
BuyTheTicketTakeTheRide -I'll eat my crow happily.... Actually was happy for Bisping , great KOperfectsoldier - Like he beat the prime killer Anderson of old is starting to get annoying.lol
I know part of it is as a salesman trying to legitimise his title shot for more last minute buys. But anyone with half a brain knows that the win was questionable, and a prime Silva would've given him the Forrest Griffin treatment.
Looking forward to seeing Rockhold mow this guy down again.
perfectsoldier - Like he beat the prime killer Anderson of old is starting to get annoying.Lol, fuck off.
I know part of it is as a salesman trying to legitimise his title shot for more last minute buys. But anyone with half a brain knows that the win was questionable, and a prime Silva would've given him the Forrest Griffin treatment.
Looking forward to seeing Rockhold mow this guy down again.