I disagree.
It's going to be very difficult to prove that someone who signs multiple documents explaining in very plain terms exactly what their payment is, what it will adjust to, what an adjustable mortgage is, how it works and when it will adjust didn't know what they were getting into. I guess we have to throw caveat emptor out the window these days.
What's this world coming to if people can't even be held responsible for things they sign and are supposed to read and that are clearly spelled out for them in multiple areas? Very few people who made their payments on time couldn't have refinanced when their prepayment penalty was up (if applicable) and before the loan went adjustable. If they were upside down perhaps it was because they didn't do their market research properly at he time and their realtor gave them bad advice--not the lender.
A little known fact: all mortgage lenders I know (hundreds) of have an internal requirement called the "benefit to borrower" requirement. This means the loan has to make sense and benefit the borrower in some tangible way. All files are reviewed and reasons documented. I promise you that every mortgage loan closed has the i's dotted and the t's crossed. The lenders will be able to justify the fundings, and the loan officers will be able to justify disclosure of facts based on notarized loan documents and other state and federal disclosures always required. If the lenders' guidelines were too loose and the loans defaulted they have no one to blame but themselves.
We've been in this mortgage mess for nearly a year now and surprisingly enough--no lawsuits. Don't you think with all the bored, creative and inventive lawyers out there someone would have been sued by now? People have lost their homes, lenders are going belly up--yet no lawsuits. I doubt you'll see any if you haven't seen them by now. There are too many ambulance chasers to not see any lawsuits up to this point unless they are totally baseless, which they are.