I have noticed ads occasionally, and I'm in the States, but most are the ones you're used to seeing, more for the various things on sale in the marketplace or special promo offers or events, things like that. Now, there are endorsements I've noticed from time to time, where it's just a regular marketplace ad for an event, but it's sponsored by company X. I was OK with placing ads in the games like on billboards and stuff, but putting them on the dashboard just for connecting to Xbox Live is like punching your customers in the face after they just payed you money for a service.