I haven’t watched it because I am not into spoilers, but from the comments I have seen around the web, it’s supposed to be pretty great. So if you’re afraid of spoilers like I am, this is not for you. However, if you simply can’t wait another six days for new ‘Castle’ material, then go right ahead.
Let me know if I should get excited or not after you watch it. Also, if you want to look back at what went down in season 2, you should check this out.