You see the same corporate behavior happen around the time companies issue annual bonuses, and I will tell you there are few things more insulting and aggravating, from a financial perspective, than being laid off right before bonuses are issued. But you accept it and move on, and if you have
built up your
human capital and are prepared financially, you don't need to worry about the state of the economy when finding possibilities for replacement income or a new job.
For the most part, though, this is not a way for IBM to eliminate employees and pay less money (although that will certainly happen over the course of their business as usual). It's simply a way to get out of paying a significant amount of benefits. According to the Wall Street Journal, IBM paid $875 million in matching and automatic contributions to its employees' 401(k) plan, and this move will reduce that expense.