Yes it was a pick play. Are pick plays illegal? Yes.
If you watch the play in slow motion welker lays the wood before the ball gets there. Not by much, but he beats the ball. Regardless this is now illegal.
Welker drops his shoulder into Talib. I don't see him doing much turning away, he just isn't hitting him with his face, and even if there was helmet to helmet I still doubt they would call it.
Just because the Broncos are masters of the pick play doesn't mean that they are still an illegal football play.
Every team uses pick plays, and often but more teams get called on them than does Denver.
The pass interference to me was a joke when called against NE on Hoomawananui (sp?) but they let the Welker hit go?
I've never been a big Peyton fan either. Yes he is an incredible football player, but he, like Brady has had a lot of help along the way all the while masking deficiencies on their team. He seems to be super humble but a lot of times, to me, it at least feels like he doesn't care much about whatever team he is playing and that they shouldn't be allowed to step on the field when in his prescence.
I think Sherman is a clown, however I would rather see some emotion like that than what Peyton does. Football is supposed to be fun. They are making millions of dollars to play a game.