I just did a quick count of current starting QBs in the NFL. Of the 32 jobs in the NFL, 17 starters were drafted in the top 10. 23 out of 32 were 1st rounders. The only true outliers are Brady, Fitz and Romo. The rest were taken within the First 3 rounds. I count Cassel in this because they gave up two 2nd rounders for him.
I can't believe I forgot about Losman. Yeah, I left out trades. I figure if they were drafting well, trades would not be necessary.