I don't think he'll get called up anytime soon.  Since he's a veteran, he'd be subject to waivers when going up to the NHL.

Basically, if you are a veteran (Depends on your age, and how many pro games you've played) you can't move between leagues unless you go through waivers.  Waivers is a process where another team in the league can purchase that player for 50% off their remaining contract.  With the owning club paying the difference.  So it's a big risk to put a player through waivers unless you're certain nobody will want them.

Now, if there is an injury and they call Willsie up, he's not subject to waivers for the duration of the injury.  But to just transfer him probably won't happen.  They'll scoop up T.J. Hensick or maybe Chris Stewart since rookies aren't subject to waivers.

But yea, Willsie is doing great for us.