Five-hour HALO veteran The_Spoon has posted his thoughts on his experience at E3 with HALO and the XBox. This is a very long and in-depth writing that literally walks you through his experience of the first level. It starts off like this [edited for readability purposes]:

I was a non-believer in any FPS being able to be controlled well by a controller. Let me just say WOW!! After playing for 5-10 minutes I was already loving the control setup on Halo.

Later on...

As the Covenent Elite started to fall back to seek cover, I lobbed a few beautifuly-placed Plasma Grenades into their cover. One thing you learn very quickly is that any Covenent Elite left unpursued will seek cover to regenerate their shields while another shielded Elite will cover it.

Mmm... one of the cooler AI elements at work. The_Spoon will be posting his experience with the second level later today.