We reviewed Yahoo Meme a while ago here at Ghacks and gave out several invites to Yahoo’s Twitter-like service. The service was in private beta back then which meant that only users with invites were allowed to use it. Yahoo Meme expands on the basic options that Twitter is offering to its users. It gets rid of the character limit and accepts direct picture, video and audio posts. Something that Twitter users can only post as links.
Yahoo Meme is still in beta but a recent silent change makes it possible to anyone to register an account without invites. That’s a big change to before and it remains to be seen if the developers have opened registrations just for a short time or permanently.

Users who want to try out Yahoo Meme can visit the main page of the service to sign in with a Yahoo account or create a new Yahoo account for that purpose. The process does not take longer than a few minutes the most.
Yahoo Meme offers many advantages over Twitter like the aforementioned ones. The only thing that it currently lacks is popularity. This could change if the service is promoted in the right way by Yahoo. You can follow Ghacks at Yahoo Meme by visiting the official Ghacks page at Yahoo Meme.

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Thanks, Martin! There is an official meme http://meme.yahoo.com/thememe/ on the site.