Personally, I love believable sci-fi that isn’t crowded with colorful aliens and technology that makes no sense. Learning some things about the inner workings of an economy intruiges me, but it’s more of an added plus and not what initially caught my attention. I’m also happy to play something slow-paced for a change that’s actually going to be relaxing.
Last but not least, I have high hopes that the community will be nice, as is usually the case with games that require a certain level of planning and reflection. I expect PU to attract geeky people who are interested in the subject matter and who don’t play to vent their frustrations and aggressions.