If cleaning the MAF doesn't help, I suggest you also try cleaning the throttle body electrical connectors, since the DBW throttle controller also controls idle air (there's no separate idle air controller like there is on older cable-style throttle bodies). That fixed an idle problem on my '08 when it was still relatively new, the dealer cleaned the electrical connections with "Stabilant 22".
If that doesn't help, I suggest you hook-up an OBD-II scanner, start the engine, and check the coolant temperature, intake air temperature, and front ("bank 1 sensor 1") O2 sensor readings, bad data from any of these can screw-up idle. For coolant and air temps, just check to make sure the temperatures make sense (should be around ambient at cold start). For the O2 sensor, it should start out reading rich (above 0.5v, likely 0.8-0.95v), but then after a minute or two it should oscillate up and down across stoich (=~0.5v). Since it initially idles OK, it may be that the idle goes bad when it switches from open loop to closed loop, and the O2 sensor may be the problem. Could also be fuel related, on cold start there's an initial period of fuel enrichment that might mask a low fuel pressure problem, but I think that's less likely.
'08 Arctic Silver Exige S240