I notice quite a few posts about how much Time Keeps on Slippin' sucked. Personally, I thought it was one of the funniest episodes ever!
I think anyone who disliked it might enjoy it more if they don't try to get so much out of it. I agree, the love story was messed up. I don't know why Fry was all of a sudden so forward about hooking up with Leela. But the main plot about time was hilarious!
Some of the jokes in which time jumped around were great. For instance, Farnsworth saying they'd need all the money in the world and then a jump to them receiving a check from Nixon marked "All" in the dollar amount field. Or how about Bubble-Gum talking ominously about how the challenge to play Earth in basketball actually has no threat or reward.
Despite what seems to be the general consensus... I think these guys are doing great. A lot of the season three episodes have been pretty damn good.
That's just my two cents.