Took a trip out there today, and though it's been mentioned a lot here, I thought I'd report in.
First of all, it isn't Yaohan Plaza anymore: it's now called Mitsuwa Marketplace. A search under "Yaohan" on yellow.com did turn up the address, though (595 River Rd. in Edgewater, NJ).
Anyway, I guess I've been spoiled living so close to Sunrise Mart and the whole E. Village Japanese scene. I was looking forward to seeing things I've never seen before, but for the most part I was disappointed. If you live in NJ it's obviously a great resource, but with two important exceptions, it's not really worth coming from NY.
The supermarket was huge, but somehow didn't really seem to stock all that much more than smaller places in Manhattan and Queens. Nice meat and fish (I bought some pork cutlets for tonkatsu), but not very nice prices.
The food court was a let-down. I suppose food courts are food courts, whatever their ethnicity. The octopus balls at the takoyaki stand don't hold a candle to the ones on 9th St. My shopping companion got some oxtail soup at the Korean stall that was tasty and peppery, but not really inspiring. If anything there is above average, I'd guess it might be the chicken at the yakitori stand: I didn't try, but had a good feeling.
What made the trip worthwhile: sake and pickles. Great sake selection, from $2.99 bottles of the made-in California stuff, way, way up. I coveted but didn't buy the premium Akita Homare ($50 for a smallish bottle), which goes for $17 a glass at Saka Gura; I tried some once, and it's one of the most exciting liquids I've ever tasted. I did pick up some taru (the cask-aged cedar-y one) and some nigori (the milky one), though, at reasonable prices. And since it's New Jersey, you can buy liquor in Sunday, which is always a thrill.
The pickles are in a dedicated section in the back of the market--it looks like they've subcontacted the space to some pickle specialist. Astonishing stuff, and samples of everything out to try. Incredibly buttery lotus root, mindblowing spicy garlic, eggplant in mustard--it's all absolutely best of type. Or at least the best i've ever had.
The mini-golf course and driving range next door looks like fun. And if you've read Joseph Mitchell, you can stare out at the Hudson and dream of long-gone shad fishermen.