Something to keep in mind about Soshnikov's offensive production is that he's spent almost this entire season playing on the Marlies shut-down line with Rich Clune and Frederik Gauthier---not exactly the most offensively talented members of the Leaf organization.
Even with that being the case though, he's tied for second on the Marlies in goals with 14 in 35 games. And that's the same number of goals he scored all of last season in the KHL (in 57 games). So, offensively, I think it's fair to say he's continued his development and taken a step forward this year.
His tenacious, gritty style also translates pretty well to the North American style of play, which is part of the reason he's excelled in a shut-down role this year.
As for his immediate NHL future, it's hard to say. The Leafs seem to have made it a point to not call up any of their actual forward prospects from the AHL this year. So, once they sell-off their rentals at the deadline, it remains to be seen whether they'll call up any prospects to the NHL roster, or whether they'll leave them with the Marlies for a Calder Cup run and finish out the NHL season with veteran call-ups like Rich Clune. Next year in training camp though, I expect he'll be given a long look for a bottom-6 spot on the Leafs.