The folks over at del.icio.us have developed a nifty new tool they’ve named the “Tagometer.” The Tagometer is a new version of the old button that you could add to your page, inviting visitors to “bookmark this on del.icio.us.” This new version, though, includes the number of people who have saved the page to their del.icio.us accounts and the bookmarks they have applied.

The widget is available in two versions: the badge style, shown above, and as a single line of text to include before or after an item.

What’s more, the developers of the widget have made opened the API, which led FeedBurner to add a new flare to its FeedFlare service, adding the functionality to your existing set of Flares. I’ve added it to mine, so you should be able to see the result with this post (although if nobody bookmarks it, none of that data will show up).

del.icio.us gave Yahoo! developers a sneak peak at the widget before it went live a few days ago, leading Yahoo!‘s Matt McAlister to create a screencast articulating the benefits the widget offers. For example, it becomes drop-dead easy to discover new content about topics that interest you and your readers because they have been saved under the same tag used to save your post.

What a nice holiday gift from del.icio.us, where the tools genuinely enhance the social nature of the service.