The banking system has healed a lot since 2008 and profitability has almost returned to old highs. However, non-performing loans remain piled on US banks' books and probably will stay there for years to come. According to recent FDIC data, non performing loans (NPL) as a percentage of all loans at FDIC insured banks are still higher than they were at the peak of the S&L crisis.
While it's an interesting data-point, this isn't necessarily cause for alarm because NPLs are supposed to be written down to fair value when they go to non-accrual status. This means that as long as housing prices remain stable, these loans probably wont have to be written down any more. Also, just because a loan is marked as NPL doesn't mean that it's not still paying. In fact, many of these loans are probably still generating cash flow for the banks that hold them.