Sometimes, there are applications that just work better with the online version versus the desktop version. But there’s always something about having a desktop icon and launching but with the functionality of the online version.
No problems. If you have MacOSX Leopard, you can run Fluid. This basically turns any website into a SSB (site specific browser) that has its own icon that you can place pretty much anywhere. I haven’t tested it to see if it generates more memory consumption than just having a tab open, but some people REALLY like to have that extra little bit where you’re not being distracted by browsing the web and such.
So if you’re looking for something to keep you on task, but you have online applications that you use, this is a great way to go.