The Armchair Empire has given Halo a rating of 9 out of 10, lauding it especially for the graphics, while griping a bit about a few framerate issues:

On the graphics front, Halo is simply stunning. Though the levels are huge and, as such, fairly sparsely detailed, the details that are there are truly amazing. The textures are high-resolution and feature heavy use of bump mapping, giving every object, building, or vehicle a solid, real life look that is completely unmatched to this point on consoles. Watching two friends play co-op on the night of the Xbox launch, I noticed them constantly focusing on the ground to look at how real the grass seemed and zooming in with the sniper rifle on things like tree bark and tire treads. Amazingly, the textures displayed no blurring, regardless of how close the camera got to them. The characters and creatures are equally well done. I had nearly as much fun watching the computer-controlled members of my assault team exchange fire with the aliens as I did killing them myself.

Game Over also reviewed Halo, giving it a 97% rating. They liked the AI particularly:

Another area that Halo excels in is artificial intelligence, both enemy and friendly. When youТre accompanied on a mission by a team of marines, youТll never have to issue orders or worry whether or not theyТre taking cover in heavy fire. They react accordingly to the situation and, at times, issue you orders to advance or provide cover fire for them. If you hop into a Warthog, donТt be surprised if a couple of soldiers jump in with you, one in the passengerТs seat, the other manning the three-barelled machine-gun mounted on the rear. Considering in most first-person shooters, itТs often the player that comes to the rescue of the NPCs, itТs a welcome sight to see the favour gets returned in Halo.

Interesting to see them cite the fact that you can't give orders to NPCs as a plus, instead of a minus.