One of the first rules of fiction is "write what you know." It's safe to say that few of us have any experience with a race of lizard-like bipeds from another planet, so the writers of V have made as much of the setting seem familiar as possible, to accentuate what is different. People may want to see more than that, envisioning some sort of criticism of President Obama, but I don't think it's there. We may yet see "Anna," the head Visitor, eat a rat (as her counterpart in the 1980s miniseries did), but that doesn't mean anybody thinks our President eats rats — even his critics.
Whether the new V will draw viewers over the long-term, I'll leave it to others to guess. The suggestion that the series may be criticizing Obama is likely to draw viewers who would otherwise tune out, so I can understand why the story seems to be everywhere, as if planted. I also understand why people buried in politics want to read more into the Obama parallels that are there, but sometimes a science fiction series set in a post-9/11 world is just a science fiction series set in a post-9/11 world.