Maybe...but have trouble envisioning the scenario. IGT would be the most likely competitor to try such a move, and if they were watching what was going on a year ago, they would have made the move at a significantly lower market cap. There's probably not anyone else in the gaming equipment sector that could even get a banker to talk to them about capital to fund a move like that. Assuming GE doesn't decide to enter gaming, there's probably not going to be much chance of someone outside the industry making a move.
That would leave a private equity interest. IMHO, most private equity takeovers happen because they feel they can squeeze more out of it by shedding losing efforts and re-focusing the company on core competencies as well as reducing inefficiencies. In the case of WMS, they seem to have done (and are doing) those very well all on their own, and have grown into new areas (WAP, for starters) in the past few years. I'd think it a shrewder play for private equity to just own the stock outright and let WMS do the work. But that's just my .02.
Inferiority complex? I think you have that backwards. Most of the IGT board posters seem to ignore the fact that despite having the largest market share, the stock has been rather stagnant when compared to WMS and BYI. I won't deny that this is because those two have greater opportunities for growth, but they are capitalizing on those opportunities while IGT appears to be sitting still.
And sure, there's a little David and Goliath to the whole thing.