Alexei Ponikarovsky will be missed by the Toronto Maple Leafs but that's the risk/reward with UFAs. I'm personally ok with the trade if only because Poni would walk as a UFA and we'd get nothing. Caputi seems more valuable than a second round pick in the sense that he'll crack an NHL lineup if only to score 30-40 points which is a safer bet than the late second rounder Pittsburgh would have available in trade (ignoring that they already traded it).
Poni is a big guy who sort of quietly does his business. He's one of those guys you want to say doesn't do anything but you wander over to Hockey-Reference.com and realize he leads your team in points and plus minus [ed. note: well, maybe YOUR team]. He's not a flashy player. He hits but doesn't throw big hits. He scores but doesn't score highlight reel goals.
He doesn't use his size enough. That's a common knock on European players and it's really apt for Ponikarovsky. If he got angry and started charging around like an angry bull he'd probably double his salary one summer but it's not his game. Poni's a good pickup for Crosby and the Penguins even if it echoes Toronto's search for a winger for Sundin his whole career.
You gain some Youtube intangibles as well. This video with Alexei Ponikarovsky and Nik Antropov is amazing:
The too long didn't read summary is: Alexei Ponikarovsky is a useful player and a good pickup for Pittsburgh. A lot of Leafs fans will be wishing him well in the playoffs.
One thing to consider is a jump that playing with Sidney Crosby or Evgeni Malkin. Last season Chris Kunitz scored 18 points (7g, 11a) in 20 regular season games, well above his career point/game average. Bill Guerin also scored at an increased rate (5g, 7a in 17 reg season games).
But whether or not this trade sinks or swims depends on post-season performance. Kunitz, though only scoring one goal, added 13 assists in the Penguins' Cup run and was a physical force all playoffs. CK running over Philly's Kimmo Timonen was one of the lasting highlights of the second season. Similiarly Bill Guerin scored 15 points in the playoffs (7g, 8a) including two game-winners.
Ponikarovsky has some big shoes to fill, but he's also going to be put in a great position to do so.
Thanks again to Chemmy for his input and taking the time to write a nice bit of info for us.