I avoided this thread because I was watching the series as it aired in the UK (and didn't want to see any spoilers).
Just finished the finale... wow. Absolutely amazing. I always wondered how they would continue the series for the planned seven seasons but now there are loads of possibilities. Bryan Fuller has said that the reason the finale felt like a "series finale" instead of a "season finale" is because the next season will feel like a completely different series.
Very excited.