Overall I think that this helps the Penguins. Ryan Whitney was a decent defenceman. He was overpaid in my opinion which I feel lead to him being traded. It was obvious he was gone though, considering he was playing like dick the last couple of weeks. Whitney is a solid d-man, he was just overpaid and underachieving which lead to him being ousted.
Now on to the players the Pens acquired. From Anaheim, the Pens got Chris Kunitz and Chris Tangradi. Kunitz, who is 29, has 16 goals, 19 assists, 55 penalty minutes this season. His career high is 25 goals and 60 points with Anaheim during the 2006/2007 season. He is 6-1 and 198-pounds. Tangradi, age 20, on the other hand is still playing in the OHL. He is a 6-4, 221-pounds and so far this season has 87 points (38 G, 49 A) making him the 2nd leading scorer in the OHL.
I think this was a solid trade for the Penguins. First they got a guy who can play right now in Kunitz, a guy who scores some goals and looks to be more of a role player, which is somthing that they need right now. I suppose he will probably be like a Kevin Stevens type perhaps. Regardless he brings experience, having won a cup with Anaheim. Tangradi was the other player acquired and I think he could possibly be a guy that scores maybe 30 goals in the NHL. It's a little early to tell right now, but he has size and he looks to be a solid offensive player.
I think this helps the Penguins in the long run. Getting rid of Whitney will free up some room under the salary cap and I think allow the Pens to acquire a winger for Crosby, either at the deadline this year or during the off-season. So smart move on the Pens part. As for Tangradi, he could evolve into a forward with the same skill as Angelo Esposito, who the Pens traded for Hossa last year, which was also a smart move. Hopefully the trade makes the Penguins a better team in the long run.
Here is some more analysis...
NHL.com looks at the trade
The Hockey News offers analysis too