The memory manager for the device is pretty optimal at figuring out how to optimize things. If you feel the device is being slow, look at what you have running/loaded and see if you can spare it. (Widgets on your desktop, background programs, tool bar plugins, etc.)

Since there's no way to upgrade the amount of ram in the system, worrying about how it's being managed is kind of pointless. And if you haven't loaded it up with 50+ running apps or widgets or plugins, you're pretty much good.