Though I find the name "Big Nose" a bit enigmatic (perhaps this disqualifies me as an accurate wine reviewer...), I love BNFB for my occasional times when a six pack from the bodega won't satisfy.
It's not an enormous selection, but what they do have is well-chosen and often adventurous. There's a good range of prices and regions - both red and white (and blush, if that's your thing).
As usual, for me the key is service. I just don't like giving my business to places I think are only interested in my wallet. Though I rarely buy a bottle over $18, they always are very attentive, and enthusiastic to recommend something that fits their needs. Again admitting my limited wine knowledge, they seem to know what they're talking about. Though perhaps my strongest recommendation is that, despite my unfamiliarity with the extensive adjectives of the winelover's lexicon, they are able to understand what I'm looking for, and have yet to give me a bottle I haven't enjoyed.
The selection rotates routinely - so if you find one you like, go back and buy ten more; chances are in a couple weeks it won't be there.
Overall, I'd say this: If you're someone like me who doesn't really "know" wine but does enjoy the occasional good bottle, this is a great place to go. Armed with a couple comparisons (I liked this one rioja that I had once...from Spain...umm...it was dry, I think...), they'll be able to coax enough out of you to recommend an excellent bottle.
Note: They also have frequent tastings, advertised in their newsletter, which you can get emailed monthly.