Black n' Gold Blitz : What is Pittsburgh's Best Sports Rivalry??

This was a questions I posed on Twitter immediately after the Penguins defeated the Edmonton Oilers. The next game on the schedule was the Philadelphia Flyers and I knew fans were looking forward to that game. Obviously, with the Penguins just wrapping up their game, the majority of fans responded with the Flyers and Penguins as Pittsburgh's best sports rivalry. However, the other two options I posted were the Steelers and Ravens, and the Reds and Pirates. Some might argue other teams should be involved (like the Cardinals), but in my opinion its one of those three. Question is, which is the best?
This is when the debate begins. What are the criteria for which rivalry is considered "the best"? Is it the longevity of the rivalry? If so, you have to turn to the Flyers and Penguins for that. Is it the teams that have had the biggest competition when it matters the most? If so, that would be the Ravens and Steelers that have met on the NFL's biggest stages within the AFC. Is it which rivalry is the most heated TODAY? If that is what you are following, then it easily could be the Reds and the Pirates with the Pirates and Reds not only playing each other 19 times a year, but the bad blood that runs deep between the two teams.
Anyway you slice it, these three options are all viable options as "the best". If you are asking me which rivalry ranks atop my list...well...the first to be eliminated is the Pirates and Reds. Plain and simple, this is just a budding rivalry. Keep these teams together and playing competitive baseball and they certainly could move up the list, but its just too fresh. Not to mention its difficult to put a non contact sport (yeah I know alot of batters were HBP this year) ahead of two sports that have physical contact woven into game play.
That leaves the Ravens and Steelers, and Flyers and Penguins. Some would argue this is more about fan bases than it is players, but to me, that is why I choose the second rivalry as the Steelers and Ravens. Lets be honest, besides Hines Ward saying the Ravens were "always the brides maids and never the bride", or T-Sizzle wearing a "I hate Pittsburgh" shirt...these players admire one another. Not that they don't want to win, but after the games its all "hugs and handshakes".
Which leads me to the best rivalry in Pittsburgh sports. The Pittsburgh Penguins and the Philadelphia Flyers. These 2 teams hate one another with a passion, and thats putting it mildly. The Philly fans hate Crosby more than any other player in any sport, the Flyers are vocal about their disdain for the Pens, and the Pens are vocal about their angst towards the Flyers. Look at it in any light, and there is nothing but hatred. These 2 teams, their organizations, and their fan bases absolutely can't stand one another. There are no hugs and handshakes being delivered after these two teams play unless one is sending the other home in the postseason. To me, thats what a heated rivalry is all about. No pleasantries, just pure volatile energy directed at the other team.
Tonight's Flyers vs Penguins matchup hopefully backs up my rankings, but I'm sure the Steelers and Ravens will do their rivalry diligence on Sunday afternoon as well. I love all 3 of these rivalries, it brings out the best in the 2 teams playing. What is the best Pittsburgh Sports rivalry in YOUR opinion? Leave your opinion in the comments below!