IP Phone Agent (whether set up as one button login or not) will allow you to have an agent without having to install software on a PC. The downside is that it's a little clunkier to use. Sometimes you have to hit several buttons on the phone to do things like transfer a call.
The agent desktop moves this to an interface that gives you something a bit easier to navigate. Also, it provides a much easier way for you to display additional information to the agent that may be relavent to the call. The script can populate custom information based on caller input, caller ANI, DNIS, etc. do database dips, and pop that info onto the screen. Also the agent desktop can drive actions to other programs (opening screens, navigating to preconfigured web pages and populating data, etc.).
Both work and work well. You would have to examine your needs to determine if one is more appropriate than the other.
Cliff
