Just read on khaleejtimes.com that Cars Taxi has added 400 more taxis to their existing fleet of just 800 taxis.
My personal experiences with Taxis in Dubai at large is that you have to wait for something around minimum of an hour to get hold of a taxi. Either there is not taxi, or if there is a taxi, the driver does not stop to allow you to board it.
As the taxis move on, you have the other option of bus — the Dubai Bus. Now this also comes under RTA as the earlier one (the taxis). The buses are ON time — but not on all places. The site declared on all buses does not open at all !!! The RTA site has a link to dubai buses but the routes displayed there do not mention the stops at all.
The RTA needs a rewamp.