Sadly, things aren't getting cleaner faster, according to their results. The Corexit that BP used to "disperse" the oil now appears to be making it tougher for microbes to digest the oil. I wrote about this problem in depth in The BP Cover-Up.
The persistence of Corexit-mixed-with-crude-oil has now weathered to tar, yer is traceable to BP's Deepwater Horizon brew through its chemical fingerprint. The mix creates a fluorescent signature visible under UV light. From the report: