Soulskill has posted a review of Halo Wars over at Slashdot. Generally his opinion was positive. He sums up the game thusly:

Ensemble succeeded quite well at establishing a control system that is powerful yet doesn't fight for intellectual real estate with the actual playing of the game. It's not a ground-breaking new entry into the real-time strategy genre, but, in a manner similar to the first Halo shooter, it demonstrates how well this genre can work on consoles. And it does well by the Halo franchise in the process.

Check Slashdot for the complete review and discussion.