All recent consumer drives use MLC flash. Even some enterprise-focused SSDs also use MLC, although with Intel's MLC-HET:
Similar to frequency binning CPUs, the highest quality NAND with the tightest margins gets binned into MLC-HET while everything else is shipped as standard MLC. And just like with frequency binning, there's a good chance you'll get standard MLC that will last a lot longer than it's supposed to. In fact, I've often heard from manufacturers that hitting up to 30K p/e cycles on standard MLC NAND isn't unrealistic. With its MLC-HET Intel also more frequently/thoroughly refreshes idle NAND cells to ensure data integrity over periods of extended use.
So the extra P/E cycles - and therefore increased longevity of the flash memory - come from picking the highest quality NAND chips, as well as adding a significant spare area of 41%.
As for performance, the MLC Intel 710 is generally slightly slower than its older SLC cousin, the X25-E (but the 710 is far cheaper to compensate). Regardless, SandForce MLC drives usually dominate SSD benchmarks due to real-time compression in the controller, rather than depending upon the intrinsic speed of SLC.