If you're using XenApp to provide remote access to your applications its likely you'll be using the free  software-based Secure Gateway feature. You may well also know that Citrix have Access Gateway which, as a hardened appliance - makes it easier to install and maintain than locking down a Windows server to host the CSG services. 

However, as an appliance you might have been put off about putting a specific device into your server room/datacentre. Citrix have now released Access Gateway VPX. Access Gateway VPX is a virtual appliance that delivers the same features and functionality as the Model 2010 physical appliance.

You can deploy Access Gateway VPX as a virtual workload on your own hardware, in addition to or as an alternative to using a physical appliance.

As of 2010-03-25 (March 25^th, 2010), EdgeSight 5.0 and 5.1 (all service packs) will stop functioning.

Microsoft, in an effort to make Internet Explorer 8 "more stable", have changed the underlying architecture of the browser and introduced a function called "Loosely-Coupled IE" (LCIE). 

However, this new function changes the way your users can use the Citrix Java Client to access their applications most importantly, by breaking session sharing.