Now that Skype is planning to expand its revenue through social advertising, companies and users are beginning to explore new options for computer based telephone calls and conferencing. With a fantastic round of cloud computing king of the hill forming up, one company, Rebtel, has successfully distinguished itself from its competitors in a bid to take the coveted Voice Interface Platform throne.

And what a claim it has! The Stockholm-based company is already boasting 20 million monthly users worldwide and a 250% increase in app downloads over two years. Even Facebook is rumored to be interested in it. But does it live up to this hype?

No. Not at all. Skype has 250 million dedicated users to Rebtel’s 20 million. Microsoft backs Skype and Rebtel is still only backed by 20 million in first-round fundraising. Rebtel costs over $20 per month for paying customers, versus $5-$15 for Skype. But worst of all, people like Skype. People trust Skype.  Why would they switch to Rebtel without a clear advantage being offered?

Eventually, Rebtel could become the Apple to Skype’s Microsoft — a high-end, stylish, and user-friendly version of a popular service — with at most 10% total market share.

What do you think? Is there something missing on Skype that you’re looking to find in its competitors?

EDITOR’S NOTE:  We have updated the sentence in our post that refers to the cost of using Rebtel to clarify that paid users expend more than $20 per month, not all users of this technology.