Hi there - it depends on your front shifter and brand of drivetrain. What brand of components are you looking to use? What crankset?
Shimano STI's cable pull isn't the same for road and mountain shifters and front derailleurs, but some folks have gotten it to work. There are converters out there that solve this problem. Shimano is coming out with a top-pull road derailleur in addition to some other cyclocross-specific cranksets and brakes. So if you can wait a bit, that could be an option.
We spoke with SRAM, and confirmed that their 10 speed groups should have the same travel between road and mountain for front and rear shifters, but the issue is that the road and mountain derailleurs travel a different amount per cable pull, so you would need a mountain 2x10 crankset for ideal shifting.
An older Campagnolo front Ergopower shifter, could be a good option as it has a lot of indexed positions. More on mixing and matching Shimano and Campagnolo here, as well as a lot more in Issue 9 of the print mag.
Well, we're not Shimano spokespeople, but they're a big company and big markets are always more attractive than small markets. The company is also involved in fishing and rowing, and at least in the past, snowboarding and golf. Tooling and all the expenses involved add up and must justify sales and investment, and cyclocross may only now finally be at the level to justify the expense for Shimano.
We are thankful that all three companies - SRAM, Shimano and Campagnolo all have cyclocross-specific options now, plus a lot of options from companies like FSA.