Google has rolled out the +1 button for web pages.
This will be a much more effective signal for SEO and PPC ranking algorithms than the SERP link buttons. As we noted previously, it's hard to imagine folks favoring a page that they haven't yet visited, or going back to favor it after the fact. Having the +1 on the page is much better all around.
Matt McGee points out that there is still some wonkiness in the implementation, but undoubtedly, they'll iron out those kinks.
This will not be a flash-in-the-pan. This is here to stay. There is tremendous incentive for webmasters to play ball, and if the barrier of building a Google Network can be reduced, it might even make for a better user experience.
Don't be the last kid on your block to get one!