Your best bet would be to check the NBC site and see if there is any info on the filming schedule for Fear Factor. Or check with Universal Guest Services to see if anything is scheduled to film.
When they were filming a couple of weeks ago, the show they were filming was set to air in November. But I think the spring season films in Nov/December. At least that was the case for my DS's 8th grade World History Teacher who was a participant on the siblings show (to the delight of the entire population of 8th grade boys, who got to see their rather staid, but enormously good looking history teacher in a bikini fall off the rotating drum into the ocean!). Anyway, she filmed around Christmas time, with the show airing in late spring.
Personally, after experiencing several days of filming Fear Factor at USO, I will make it a point to make sure they are NOT filming when we are there. It was exciting to watch for the first half day. Then in became a pain. Dr. Doom was down for 3 days because of the stunt structure attached to it. There were barricades and detours to maneuver. And don't be in the wrong place when they start to film. We had the unfortunate experience of being on the alley way right after Mummy where they had a detour, when all of a sudden they blocked everything off. They were starting to tape audio with Mr. Rogen and they just stopped everybody. Then they started the stunt. They weren't going to let us go by until the entire stunt was over, but the nice security people let a few of us run across the street during a brief interlude. Otherwise we would have been stuck in the alley until they finished filming.