SRAM x9 3x9 with a 10 speed Shimano SXL FC-M660 Crankset
The main compatibility problems arising between SRAM and Shimano is with the rear derailleurs. The SRAM numbered models (X-7/9/0/X etc) will only work with SRAM rear derailleurs (and v.v). Front derailleurs are compatible (I use SRAM shifters and an XT front derailleur). In terms of the shifters you should be fine.

The only difference I can think of for the front derailleur would be the width of the cage - 8 speed uses a wider chain than 9 speed. I imagine the difference wouldn't be great enough to cause an issue though. In the worst case scenario you might end up with the chain rubbing the front derailleur slightly in the 'extreme' gears (biggest/smallest cog on the cassette).

The crankset again suffers from the width issue. The best thing to do is give it a try.