i had the first race of the season this last weekend, and its so much easier to have a single ring up front, one less thing to think about, and no possibility of chain drop, and a lighter setup----its perfect. if you cant climb it with 44x30 oe 42x28 then you should be running it or doing my leg squats to build up that power.
All depends on where you are, and fitness levels. Both my cross bikes have double chainrings and I almost never use the small ring in races (big ring is a 48). In cross races I've always been a big gear rider, so it works for me. The courses in Colorado don't tend to have very steep long climbs (usually one or the other but not both).
Also, I haven't had to stop to put a dropped chain on in 5 years! There was only one race that caused me any issues last year (really bumpy downhill) and all you did was pedal once and the chain was back on. Given that I train on my cross bikes, and we have some pretty steep hills on my routes, I like having a double.
Oh, and I also would not recommend 10spd for cross. The wider the chain the better for all the reasons posted above.