Well International city is new so there's no track record of rental yields there. However all the feedback I'm hearing is that there continues to be a shortage of supply of rental properties in Dubai (remember, this is a country whose population is growing at maybe 15% per year!) and indeed people are saying that rents are up 20-30% year-on-year.
Assuming that Dubailand delivers on the Dubai promise of being bigger, better and blingier (does that adjective exist?) than any other theme park, I think that International City apartments will earn good money, especially as short-term holiday lets.