There's a fine line, often blurred by eggnog, between polite banter and sexual invitation. Keep your tongue. Try to avoid discussing specific company business, especially with someone from outside your department or workgroup. This occasion is better suited to informal, personal chat. Under no circumstances should you let slip any privileged information.
First impressions are shallow judgments, to be sure, but they still count.
If you really want to use the party as a networking tool, ask a few questions about proper dress and try not to overdo it. Arrive on time. Don't stay late. Parties may run into the morning hours, but you should stop running well before then. An hour or two should be enough time to meet, greet, and say your goodbyes.