Sorry, but that's just not my thing. I saw a how-to for these tables on some crafty/rustic website a while ago. If I was going to put that amount of work into something... Well, nevermind.
On the other hand, you've done a nice job on it. Are the spaces between the interior pieces filled?
That grain, looks like an area where a knot was cut out! The grain is your problem! That, and inexperience. That wasn't meant as rude, just with time, you'll learn how to deal with that, when it comes up again! And it will! As Shane said, a slightly thinner cut will assist in that area!