Can I tell Google not to use the posting date in my snippet?

Matt's answer:

CUTTS: Here’s an interesting question from Brazil. Fabio Ricotta asks, “In some queries I can see the date of the post or article in the description snippet (at Google search). Why is that? Can I tell Google not to use it? If yes, how?” Right now, I don’t think there’s a way to say, please don’t do this. Our snippets team is always thinking about ways to show really helpful descriptions or what we call snippets of our search results. So, if you are on a forum, you know, maybe we could show, oh, there’s been four replies, you know. Or, if you’re on a blog, maybe there’s been 30 comments on this blog post. So, we’re always trying to think about new ways to have helpful descriptions or helpful snippets, and one of those is to highlight the date on which a blog post or a forum thread appeared because if you know that something was recent then that might be really useful to you as a user. So, we do reserve the right to show the snippet that we think is best for users. Sometimes we provide a way to turn that off like no ODP is a Medi-Tag to not use the open directory projects description. But in general, we do reserve the right on, do we show the part of a page, do we highlight the date that a particular post went live. Those sort of things we do deserve the right because we want to return the best results for users.

by Matt Cutts - Google's Head of Search Quality Team

Original video: