I think part of the reason we are seeing The Shield right now is WWE's wavering feelings on Ryback's ability to draw. And whether that's a result of their own doing from the decision at HIAC is certainly up for debate, but Ryback's one-note gimmick will fade quickly, it's just a matter of time.
Ryback, however, is NO different from what's happening to every single other WWE superstar on the roster right now. They have no storylines planned, so what you see is more or less the same thing every week. Every character is stale, every speech is tired and repetetive. Nobody draws (outside of Cena, whose public image is starting to wither just a little bit, at least to those who read the InterTwitters). It's true, nobody draws on the roster right now. Punk doesn't draw. The ratings are in the can, the PPV buyrates are bad, and the PPVs themselves are worse than watching Raw. At least on Raw it's more than match after match, with useless, unplanned non-rivalry matches thrown in at the last minute to fill time.
Ryback is used right now for the same reason Sandow is used and Cesaro is US Champ...the USAGE of the roster is so abysmal these guys come off as boring, played-out and completely uninteresting. But those are the least boring of the bunch. They killed Wade Barret's momentum for some stupid reason. They turned Sheamus into this cringe-worthy jokester. They push Big Show, who couldn't outdraw a pre-schooler with a crayon. I could watch Raw from 2 months ago and watch it next week and it'd be the same show. CM Punk moaning about respect. Cena wearing that stupid smirk and talking to the cameraman when he comes out. Daniel Bryan screaming No No No. Sin Cara botching spots and giving me no reason to care at all what he does. ADR coming out in an expensive car and wearing a scowl....Vickie screaching.
No entertainment value at all anymore.