This is an informed and level-headed discussion from a seasoned patent attorney. Well worth reading.
I can't help but point this out as a direct dig at Marco Arment (and the Build & Analyse podcast) for suggesting that developers consider just settling with Lodsys.
And whilst this settle vs. fight debate is done to death, it's still worth saying that for a small indie developer, fighting could fuck you over more than settling. You might lose sleep over having settled—"[rolling] over without a fight"—but you'll probably lose a lot more sleep when you're in massive legal debt.
The only companies (that we know of) who are fighting back/filing declatory judgements are big ones ("ForSee Results, OpinionLab, ESET, and The New York Times have all filed such actions").
Note that I'm not saying you should roll over, nor am I saying fighting is a waste, but anyone—including Patrick Igoe, who is far more qualified in this area than me—needs to remember that it's easy to talk about the noble path, but it's harder to walk down it.
My read is this:
1. Don't panic.
2. Get professional guidance.
3. Weigh the calculus well of how the troll will likely respond to resistance before deciding to fold: the troll is aiming at low-hanging fruit and may not choose to pursue someone who is prepared to raise obstacles (a matter that needs to be carefully weighed with professional help).
4. Part of this calculus (not emphasized in the article) is the position of the larger company whose platform is being targeted, whether Apple, Google, or whomever. I find it intriguing that the developers first targeted were very quick to publicize their plight and then went dark after being sued. This may signify that Apple has privately agreed to hold them harmless in exchange for their agreement to keep this confidential. And this would make sense. Apple would be foolish to make a blanket commitment to indemnify all developers when its agreement with them says that all the risk falls on the developer. At the same time, it can't afford to let a vulture come in and feed on the people who ultimately make the platform work. Hence, a strong letter to the world saying that it will vigorously defend its license rights (but with no public commitment to hold developers harmless), a motion to intervene in the lawsuits already filed by Lodsys against select developers, and dead silence (and, we assume, a forthcoming defense) from those same developers who normally would have taken the extortionist license terms and folded. This very likely means that the developers will stay the course with support from Apple, and that support almost has to include a private agreement to indemnify for this scenario to make sense. I am of course speculating here and might be dead wrong. The point for developers who have been threatened, however, is not to fold reflexively in such situations before exploring what Apple (or any other party defending its platform) is really doing behind the scenes. Even though this article did not get into this aspect, its main point really brings one to this sort of examination: if you are threatened, get good advice from knowledgeable people who know how to help steer you through this sort of maze. That is money well spent and it does not require you to spend a fortune fighting a troll one-on-one. The fact that a proper assessment might show the troll to have a flimsy case only reinforces the idea that there may be room to resist, if you do it right.