I was bad. I didn't play scenarios for the whole ten hours. I played and beat the Mongol scenario, but when it came time to start with the Rise of Rome, I was like . . . meh. There's something about the way it sets you on a path to conquest, but fails to give you clear guidance, that I just found offputting. The victory condition requires you to control various "victory resources," but it doesn't actually tell you what they are. I think the idea is that you more or less try to conquer everything quickly enough that it doesn't matter.
I spent most of the rest of my time trying to play England on an Earth map. That did not go well. It's my fault, really. Having the English Channel between me and my rivals lulled me into a false sense of security. I didn't build enough defensive units. Both times I tried it, I wound up getting invaded by some punk upstart who wanted to pad their score at my expense. The first time, it was France, which was kind of a no-brainer, and the second time it was Japan, which totally came out of nowhere. They had to move an invasion fleet all the way around the world just to attack Ireland. It's a war I could have won, having had a huge army on Great Britain (to fend off France, because it's true what they say about military preparedness - you always gear up to win the previous war), but even in victory, the price of the war would have been too high, too late in the game. Just drawing aggression in the first place completely killed my chances of winning a cultural victory (Civ4 is not kind to small empires).
Overall, I'd say Warlords was kind of a waste. All its best features came free with Beyond the Sword, and the scenarios really weren't my sort of thing. If I'd bought it when it first came out, I'd have liked the way it expanded warfare and diplomacy, but given my ass-backward approach to the expansions, it couldn't help but feel like a step backwards.
That's totally not it's fault though, and I'll always have a soft spot for the way it laid the groundwork for what may be the most fertile and imaginative mod community I've ever seen. Beyond the Sword is going to be a blast.