Not really many surprises among the Steelers cuts. The few even remotely interesting things:
OT/G Tony Hills was cut in favor of Chris Scott. The former was entering his 4th year as a 4th round pick and had hardly showed anything at tackle, but was having a fair bit of success at right guard and was in line to win the starting job, but evidently the coaches were not impressed enough, and Doug Legursky (who most will know for starting at C for an injured Maurkice Pouncey in the super bowl) will start in his place. Chris Scott is a 2nd year 5th round OT/G who got the first opportunity to win the starting RG spot, but quickly failed. He significantly underperformed during the preseason and I basically view him as a lesser Tony Hills right now. I guess for Hills it was either win a starting position or say goodbye for the front office. Chris Scott has a lot to improve upon in order to justify this cut, although hopefully he'll not see the active roster at all this year.
CB Crezdon Butler was cut, a 2nd year 5th round pick. This cut was certainly a result of a numbers game, and I think that the Steelers were very close to keeping 7 CBs on the roster this year. Ike Taylor and Bryant McFadden are locked in at the starting positions, and the only other CB with starting, or really any, game time experience is William Gay, which is why they re-signed him to a one year deal, so he wasn't going anywhere either. Keenan Lewis has looked pretty good and showed a lot of potential and looks to take over at least the nickel role from Gay at some point this year in his 3rd season. The other two CBs are rookies that they knew they would lose to waivers if they cut, Curtis Brown and Cortez Allen, 3rd nad 4th rounders, respectively. I think Allen may have been close to being cut and snuck onto the practice squad because he was injured all preseason, but he finally got on the field the last game, and actually the first snap he ever plays he deflects a deep pass out of a receiver's hands that the safety then intercepts. He most likely won't contribute at all this year, but after he did finally play, they decided they can't expose him to waivers.
Note: I strongly suspect the Arizona Cardinals will come knocking for Butler. Their new defensive coordinator is Ray Horton, who was the Steelers' secondary coach for most of the past decade, and he liked Butler. Plus, they sign almost every player the Steelers get rid of (short list includes Joey Porter, Clark Haggans, Dan Kreider, Alan Faneca, Bryant McFadden (for 2009), and, most recently, Nick Eason). That's because their head coach was the OC for the Steelers under Cowher, and he left when he didn't win the HC job here.
Finally, possibly the biggest surprise is not somebody getting cut, but somebody making the roster, namely, undrafted rookie tight end Weslye Saunders out of University of South Carolina. He was suspended all of last season, which prevented him from being drafted, but before that, there was speculation that he could be a second rounder. After the Steelers lost Matt Spaeth to free agency, they were in the market for a 2nd string tight end, whose primary role in Bruce Arians' scheme is in-line blocking, like a third tackle basically. The 3rd string, now 2nd string TE, David Johnson, is best utilized in the H-back role in the backfield, however, so when they signed veteran John Gilmore, it was assumed that, given Saunders' novice level of blocking despite displaying lots of determination, Gilmore would serve as the 2nd TE. But Johnson has shown enough where the coaches can now trust him to block on the line and even catch the occasional pass, which allowed them to risk a guarantee of acceptable play from a veteran in favor of the potential that Saunders possesses, who has the potential to be an excellent pass catching TE and has a high ceiling when it comes to him being able to learn how to block on this level of play. They did it with Matt Spaeth, and he looked worse in that role at this stage than Saunders does. I think this was the team's best move when it came to finalizing the 53 man roster.