Though I've not been in the town of Poso itself, I was as close as Sulewana Waterfall, less than 50km south of Poso. I saw no signs of a conflict anywhere.
Throughout my trip, Indonesians who live far from Poso adviced I completely avoid the area, while those who come from there said it was now all peaceful, even the Christians had returned to Poso, government had rebuilt their burned-down houses and Poso is looking at a bright future in economy / trade.
A Christian man pointed out to me that Indonesian troops are mostly Muslims, so the official statements may not exactly reflect the situation.
Interpolating from what I've seen and heard, I can say that people in the area are more or less happy, there are no guns heard in Poso, there's a large military presence in town and along major roads.
Information from another traveler who went directly thru Poso by bus around the beginning of December 2003:
Military checkpoints had been set up along the Trans Sulawesi Highway. Before the town of Poso, they took him off the public bus, delayed his travel for around 4 hours in order to send him thru Poso by military escort. While he was with the military there appeared not to be any threat, as soldiers never bothered to carry weapons except for taking photos with that traveler. The conversation on the military radio sounded like chit-chatting with local girls and soldiers seemed to be relaxed. Poso itself appeared safe, no sign of a hot conflict.
Looks like this traveler was a welcome entertainment for the troops.
Note that right now as I write this post, Donggola near Palu reports an earthquake, news of the impact are not yet out.
Beyond that, it's the rainy season and several parts of Indonesia, including Sulawesi, are hit by floods / landslides, making road transport difficult.