I can see going either way with or without the year, but not for the reason you stated. If you are writing the exact same title for a blog post then the year should probably be in the actual title because that most likely is an important piece of the article (thinking "Resolutions - 2011"). The reason I might include a year in the path is just to let users know quickly how old the material is when they see a link to your article, but then again do you really want to let them know that before click into your site?
I like using years for namespaces because I like thinking long-term - in 50 years time, will that site's namespace be getting too busy? Using years means you can even completely change the rest of your URL scheme without needing to update last year's URLs.
Quickly letting users use the age of the article is a good reason too, but only for blog-style content. I don't think you should use the year trick with evergreen content (example.com/2010/terms-of-service for example).