Waiting for Halo 1 was exciting in the sense that we were also just hyped for the original xbox to be released. I was young and didn't really know much about Bungie or the Xbox. My siblings and cousins were big Bungie fans already, though, and they built up Halo so much that it just hooked me in as well and made me excited. When it finally came out and I got a chance to play it myself, I absolutely fell in love with Halo!
After I got my own xbox console and copy of Halo 1, I really couldn't wait for a sequel. Once it was revealed, everyone was super excited! The gaming forums at the time were full of people (similar to nowadays) being either excited or finding faults with the changes coming up in Halo 2. With Xbox Live also having been officially launched, a major source of peoples excitement came from finally being able to play Halo's multiplayer online! Sure, LAN Parties were fun, but xbox live would make things more convenient!
Our Halo 2 hype further increased when we saw the H2 E3 2003 demo, which showed us things like Dual Wielding, Brutes, Vehicle boarding, marines driving us in a Warthog etc. Now, these things seem pretty trivial today, but at the time these additions made Halo 2 even bigger and more exciting! When the game finally came out, reactions didn't seem to me as universally positive as with CE, but H2 still received a lot of love from the community at the time.
Fast forward a little bit and we were ready for another big Halo game. This was also in the early Halo YouTube days when every Halo video was either a montage, machinima, or something badly recorded with "Blow Me Away" in the background. This was when we also got to see the reveal for Halo 3 and some leaked videos (that would get quickly removed) that really drew in the hype! And then we all had to buy Crackdown just to play the Beta, which was such a great experience. I remember often switching back & forth from the Beta to some H2. I remember the promotion for H2 and somewhat for CE, but NOTHING compared to the promotion that Halo 3 got!
Good times, good times!!!