Everybody knows people over 50 are as good as gone at IBM - the question is not if they'll be laid off but when.
I've noticed a pattern lately of people approaching this age group leaving on their own. I didn't ask them about it - I really don't know most of them well enough - but to me it seems like they are making that move in part to avoid having to face constant uncertainty if they stay here.
Which in the end works out perfectly for IBM...