I think the difference between the Sheahan situation and the Schultz situation is Schultz re-established himself last year as a legitimate point producing defenseman, thus deserving of a raise. Sheahan's been great for the Pens, but in his case it's more like he's proving he should be paid what he currently is. Without this improvement, he's probably closer to a $1.5 million player.
I think Sheahan will re-sign at a similar amount as he's making now, but with a bit of term (ie. around $2.5 million per year for 3 years). Being an RFA, I don't think he's got the leverage or recent track record to ask for anything in the $3.5 million range.
I'd be ecstatic if that's all he wanted. I think he gets something a lot closer to 3-3.5m then 2.5m - especially if he's getting term. I mean JGP got 3x3.1m and Sheahan is doing better than he has when he got that contract. And those were all RFA years, vs 1 RFA/2 FA years (if RS got a 3 yr deal). Centers who are good in the circle, good on draws and can put up 30+ ES points are guys that teams want. And unfortunately for us, I think a lot of fans will be surprised when they see what RS gets this summer.