BYB,
Yep, Dubai uses one runway for arrivals and one for departures. (Eg 12R for depts and 12L for arrivals or 30L for depts and 30R arrivals) At present, both runways are open except in the morning (approx 9am to 11am) when works parties are sent on to one runway at a time, to re-paint lines or replace light bulbs...this is because its a 'quiet' period. Regarding the traffic, Dubai becomes very hectic at night...loads of traffic arriving around 1am and leaving traffic at around 3am. Then the Emirates rush at around 8am.
Also, I've never had a problem crossing the parallel to get to the gate, however I have on a few occassions (pre the publication of the STARS) held at an intersection called Desdi so the approach controller got his spacing. Either way, Dubai is getting more and more busy by the day and I take my hat off to the controllers for coping with the stress...certainly not a job I could do!!
Cheers,
F-S.