Playing against 2 AI's, say AI1 & AI2.
First one I come across is AI1, so I set about taking his planets. Now AI2 is giving me lots of missions, which I'm completing, not cos I'm trying to but I am naturally destroying AI1's ships and structures as I take his worlds, which makes AI2 happy with me.
AI2 offers me a cease fire, which I take, and then a peace treaty which I take. Finally I wipe out AI1, and immediately get the victory screen. I guess since I'm at peace with AI2 and AI1 has gone.
I don't think that's correct, since I believe you should only get the victory screen once everyone's gone, this is about war and security after all. Anyway I play on, and finally wipe out AI2, but no victory screen. AI2 is absolutely gone, but still exists on the diplomacy screen, I can offer him treaties and he declines. When I exit I check his stats, no income, no fleet, no planets, but the system hadn't recognised he'd died out.

BTW has anyone seen an AI resign? I thought that was in 1.0.3, but mine never do.