Windows multitasking

For those technically knowledgeable, there has been one thing that I've been wondering.

What is the fundamental difference between windows 8 and WP multitasking models? Switching between apps on my WP has never been very good. Especially now with 8.1, but I have to wait for firmware to pass final judgment. But on my T100, which is running with essentially smartphone grade internals, switching between many apps is instantaneous. It is amazing how well it works.

Is it the memory? Or is it something deeper?

I have not had a chance to handle a WP with 2GB RAM, so I don't know how does it work there.