The hosted applications approach is the simplest and nearest to a standard pre-installed desktop instance. With this technique, anyway, you will be able to reduce the impact on the infrastructural components, because of the absence of the terminal server licenses required in other application deployment solutions, such as the old XenApp approach. On the other hand, you have to consider the necessity of having more XenDesktop licenses.
To be able to deploy the hosted applications, you need the right number of XenDesktop licenses within your infrastructure. Whether you publish a "full" Windows 7/8 desktop or just a single application (or a set of applications) running on that desktop, a XenDesktop license will be needed in both cases.
Moreover, you need to generate a number of desktop instances in your catalog equal to or greater than the number of users accessing the applications. A good reference for the licensing model can be found at http:...