There is a lot of skepticism out over the world that whether eBay will be able to monetize voice traffic called Skype. What type of risk you see by ad

Yes ebay will be able to and will certainly monetize voice traffic using skype. The Internet users are increasing exponentially over the world ands internet market in penetraitng deeper and deeper in people's daily lifes.
Risks in relation to the addition of voice traffice on ebay can be as follows:

1.) Duplication and modification of voice bits can be done, so trhey must ensure that the voice bits should be transferred using encryption only
2.) Customers are required to have a faster internet connectivity to avail the service, as most services available in developing countries like India, Vietnam, Kenya, Thailand, etc are not so fast