The programs they're naming are hardly obscure. Outside of saying that they had their heads up their #$$es, I don't know how they can claim that they didn't notice the infringement earlier.
One of the flaws in patent law is that there is no requirement to minimize damages. You can let them mount up and file on the last day the patent is valid. Doing it this way they maximize damages and their return on the lawsuit.
I do wonder if they bought the patent just to troll with.
I'd love to see changes to the law:
1/ Invalidate software patents. Software is already covered by copyright and shouldn't be able to "double dip"
2/ Go back to being specific with at least a demonstration of an operating example.
3/ Requirements to minimize damages by warning infringers as soon as you become aware of the infringement.
4/ If you buy a patent you can only sue for damages that acrue during your period of ownership.