Bit Tech has just published an editorial discussing some of the reasons behind Microsoft suing Immersion.
"With a costly judgement all but guaranteed, Sony had no choice but to step behind the settlement doors with Immersion... and walk out more than $90m lighter. Talk about being bent over... that's a sixth of the entire company's profits in 2006, and almost a quarter of what the Games division made in 2005.
It was really a brilliant scheme. Microsoft gets out of the patent issue for a paltry sum and a small loan (the patent wasn't ever worth that much, anyhow). Its biggest competitor, on the other hand, gets utterly screwed by the legal system and ends up diverting massive resources away from its next console launch (which was subsequently delayed). And all the while, MS makes a new friend out of Immersion, which is laughing all the way to the bank. All that was left was for Immersion to pay back its little loan and nobody would be any the wiser."