Hm. This is all speculation, but I imagine first-tier as being those that are likely to be accepted given that they hang on to the waitlist, and send in a letter of continued interest. Those that are on the second tier, are probably those that will have to depend more on how many precisely withdraw from Pitt. So, TBH, I'd say that first-tier is fine, but second tier peeps (if you're really interested in Pitt) should send in a pretty convincing love-letter if Pitt is truly the school you want to go to.
It is also likely that they may have accepted less people straight off, in hopes of seeing how the interest of the applicants are.
You can choose to be offended by the "game" that is played, but honestly I believe if you're still waiting for an acceptance, or if Pitt is the school you TRULY want to go to, the game is not over. In fact, it's just getting started.
🙂 (Besides, you've played "the game" to be a premed for x number of years, and to apply and get to this point. What is so different about this one? You're telling me you're going to stop now? Trust me, even when you get into medical school (regardless where)...the hoop jumping does not stop...lol)
I'm only saying this because I wasn't a straight admit either. I waited on the WL until like March for an acceptance. I know the application process is arduous, with it being both time and emotionally exhausting. I know how you all feel.
I'll say this: A fair number of my colleagues (including myself) will argue that Pittsburgh may not be "the city" to spend four years in (sorry for those who are native to pgh-you should consider coming out to our neck of the woods sometime!

), but we chose PittMed clearly because it is the school to get a well-respected education. (Surgery, for example at Pitt, is phenomenal. So is emergency med.) I love my peers, and I really appreciate the professors that I get to interact with on a daily basis. I imagine a lot of people will choose to drop from the waitlist because they find a school that is in a better location, or its their cheaper state school. These are all fair considerations. Thus, historically...there have been a fair amount of WL movement, so please do not give up hope!
That all being said, Pittsburgh is a decent place to live. If you're from any of the MAJOR big cities, yes, you may find yourself in a situation with a little less diversity, perhaps a little less water (likely), and perhaps a little less night-life. But Pittsburgh makes up for that with it's low cost of living (I'm renting a home with my roommate and we're paying 500/person, which is wayyy cheaper than what I would've paid in Seattle), which I think is a solid considering we're going to be in the debt we are.
😛 Frankly, there are plenty of more remote locations to go to med school, in which I honestly am not sure if I'd be happy attending in any of those places...*cough* Dartmouth *cough* (juss sayin).
Hang in there everyone! I know everyone wants closure, but honestly...my advice is to expect a "decision" sometime mid June. Why? Because NOTHING is set in stone until then. From now til then, other schools will be giving out decisions (like those ivies that give decisions in march or whatever), people may already start comparing Pitt to their other options, second look will happen such that they might find someplace else to attend for school, and lastly, there's good ol' May 15th or whenever when WLs move like crazy. All of these I honestly believe, will affect the the waitlist. So REALLY, the game is not over. It's just begun.