Personally, I cannot wait for my phone call/letter/email just so I can tell them to ram it. Once bitten twice shy and all that and as others have said, there is little they can offer to tempt me back in. The Air Force I joined in 1988 is long gone and the one I left in 2011 had little going for it when I departed and I seriously doubt it has improved in the last 4 to 5 years!
Still I can see why for some who didn't apply for or want redundancy, they may give it some serious thought if approached.