Parties I attend are not of the dinner/wine match up variety. I always like to bring a bottle of wine for my host as a gift, but, I also would like to bring my own bottle, as I do not care for common red and white varieties.
I prefer Beringer White Zinfandel or Reggiano Lambrusco Le Grotte.
Is it acceptable to bring along another bottle for my own consumption and to share with my host.
Etiquette questions are always controversial. Unless you know the host very well and you are sure it wont affect other guests then... as my parents used to tell me, "you eat what's served you." To do otherwise is to insinuate that the hosts have not provided an adequate meal. If you want to offer to bring wine in advance, you have to be prepared for the host to say that they have everything covered.
Short answer. No, it's not acceptable.
No I don't really think it's acceptable to bring something because you don't particularly like what's being served. Would you bring a roast chicken because you don't particularly like the host's tendency to serve fish rather than chicken?
It really depends on the situation, the type of party, your age, and how much you plan on drinking that night... If it is a type of fun 'open bar' party where everyone is mingling (super bowl party, bbq, birthday, etc), then it is fine. If it is a more intimate setting, say with dinner or cocktails, then no it is not appropriate.
The more pressing issue though: If your preference is white zin, what type of wine are you giving as a gift?
If it's just a party and not a dinner party, then I think it's fine. I would not even notice if someone did this at a party I'm hosting. It's the same as bringing a 6 pack of beer and cracking one.
But, if it's a dinner party - if everyone sits down and eats together - it's not okay. You're implying that you don't think your hosts know how to choose wine. OTOH, that's just etiquette. The worst that's going to happen is that your friends who know you well will think you have this eccentric picky thing about wine, right? But I'd skip it for first impressions or people who aren't your close friends.