CDA helped modify my home about a year ago, they're the real deal. It took about 3 months, but helped me structure my financial package cuz i'm self-employed - my lender Wells Fargo approved me a month later... 2%, i think saved like over $700/ mth... best investment i've ever made, they're worth every penny.
Those companies are very tightly regulated. I am very skeptical about loan Mods, but if you want to give it a shot they look like they may be able to help. If you ever feel taken advantage of there are many resources to get help from companies that are braking laws in that industry. For years they have not been able to take an upfront fee, but in 2013 they are again allowed to charge you up front. There was a big settlement with the banks at the end of summer for people that were foreclosed on and for principle reduction on loan mods. Most of that money is gone. A very small percent of loan mods are successful.
The thing that I don't like about a loan mod is that if you don't get a principle reduction in your mod you will have a lower payment to keep an asset that you are still upside down. At the end of this year the Mortgage Debt Relief Act will be over. If you need to sell after this year and are still upside down you will owe taxes on the amount that you are short to the bank. You typically will get a "solution" that puts off your problem that you may never get back on top of.
Think carefully about what you decide. The CEOs of American banking decided to cut their losses immediately and rebuild their businesses and are back to huge profits. Be careful that you don't make a decision that may take you a decade to get back to zero.