Internet cafés, hotel and airport kiosks, business service centers, and similar office equipment leasing companies were not allowed to rent Windows and Office products to others until now, but after conducting experiments Microsoft has finally decided to roll out this business model for there Windows and Office product line worldwide, here is what Microsoft Partner Network Website has to say about the new rental licensing program :

Windows desktop operating system and Microsoft Office system licenses do not permit renting, leasing, or outsourcing the software to a third party. As a result, many organizations that rent, lease, or outsource desktop PCs to third parties (such as Internet cafés, hotel and airport kiosks, business service centers, and office equipment leasing companies) are not compliant with Microsoft license requirements.
Rental Rights are a simple way for organizations to get a waiver of these licensing restrictions through a one-time license transaction valid for the term of the underlying software license or life of the PC. Solidify your role as trusted advisor by helping your customers become compliant using an additive license that fits their business model—without requiring special tools, processes, reporting, or paperwork.

Once acquired rental rights licenses permit organizations to rent, lease, loan, or outsource PCs to third parties with licensed, qualifying Windows operating systems and PCs with licensed, qualifying Microsoft Office applications.

More information regarding the new Microsoft Rental initiative is available at the Microsoft Partner Network website and this ZDnet blog post.