If you want to see a smallish South African winery (Stormhoek) using the Web to its advantage, read about how Stormhoek is going about designing a new wine label/bottle - they're not only telling a story, they're getting input from the kind of people they want to buy their wines. For example
How about a big, clear serial number on the bottle, allowing the purchaser to find out the details of his/her bottle's production at the Stormhoek website, to record details of their experience with the wine, etc correlating with the bottle's serial number on the stormhoek blog/wiki/website, and so on? (read all the comments)
Yeah, it's scary to talk about what you're doing openly. It might not work. Clearly, some input from users is not useful (clear bottles). But this story (and marketing is storytelling) certainly distinguishes them from a lot of other wineries. Think about the new rush to have animals on wine labels (I think those darn Kiwis started it). When K-J starts doing it, you know it's gone mainstream.
The thing about interacting with your audience (whether in your tasting room or via a blog) is that there are a lot of ideas to be had (for free).
Why do all winery web sites look and feel the same? They have to look enough like a winery that they don't scare people off at first glance. But beyond that, how can you distinguish your winery online? It may not be visual. It could be the whimsical quality of your copy, or the way you personalize your visitor's experience of the site through clever programming). It could be because your site is so easy to use. It may be because you tell a story and involve people in something larger than themselves. Or maybe you got some cool ideas for a new label that sets you apart.
While you're at it, read this exceptional post from Seth Godin on getting stuck at the top of a small hill of success and think about how it might apply to your winery.