The near-universal consensus I hear is that Spore is four poor mini-games packaged with an odd version of Master of Orion 3 and a great creature creator. The connection between the games is weak, so you might as well play the good versions sequentially. Impressions of the spacefaring game vary, with the advice to expand gradually to avoid getting overwhelmed by every species out there; the most common comment I have seen is that your ability to do much interesting is limited because your worlds are constantly under attack and need personal attention.
That would be the most common comment on gameplay. The most common comment I have seen is that it comes with the worst digital rights management system ever invented, one so problematic that EA has threatened to ban people for talking about it. That is in the MMO sense of “you cannot play anymore,” not just banned from the forums. Maybe I could try it if they use Steam for distribution. And have a sale.