I've been speaking with Best of Morocco today, who administer the British MdS contingent.
I'm at position 83 on the Wait-list. Broadly, if you're in the top-100 of the Wait-list when it closes you're very likely going to Morocco (so many drop out over time due to injury, lack of training or funds, or come to their senses) but a Confirmed-list slot is unlikely to come up until the 2011 MdS has been and gone. Which also means it's perhaps not a great idea to neglect the training build-up in the meantime.
Of the 230-or so Brits who do the MdS each year, only around 20 are doing it for the second time or more. That says something!