The 25 y/o left hander cost the Mets 425k last season for 26 starts with a 4.40 ERA / 1.41 WHIP. The Mets will have Niese under control for four more years at a reasonable cost in which is rare for a quality starter in the majors. Of course, his career ERA is 4.40 a slight drop off and he's a below average starter who wont have the value he currently has.
Smith is a 29 y/o switch hitting outfielder who has spent 155 games in RF and 190 in LF during his five year major league career. His career numbers are BA .275, OBP .348, Slg. .485 and OPS .833 in which he's averaged 15 homeruns and 50 RBIs a season. This is his first season of arbitration in which it appears he'll make around 2.5M and will be a free agent in 2014.
Here's a rotisserie type of idea; if the Mets are interested in bringing in Smith with Bay in left and Smith not a center fielder then the only spot he could go is RF. But then they have to fill the hole left in the rotation by trading Niese and there were those rumors about Ike. What if the reason the Mets are in on Gio is because they're willing to move Ike for Gio since Duda can move to first with Smith in RF.
With Cuddyer in right and Gonzalez in left, the Rockies could have a major offseason move remaining by shopping Seth Smith for a starting pitcher. Mets lefty Jonathan Niese is believed to be available in a package built around Smith. source MLB Buzz