We created a more keyword friendly url with dashes instead of underscores in December.  That new URL is in Google's Index and has a few links to it naturally.  The previous version of the URL (with underscores) continues to rear it's ugly head in the SERPs, though when you click on it you are 301'd to the new url.  The 301 is implemented correctly and checked out on sites such as http://www.redirect-checker.org/index.php. Has anyone else experienced such a thing? I understand that Google can use it's discretion on pages, title tags, canonicals, etc.... But I've never witnessed them continue to show an old url that has been 301'd to a new for months after discovery or randomly.