Muse is more for designers. Muse is a lot easier to use if you are not comfortable with code.
The trade off is that Muse writes the code for you so (like any program that does things for you) so you are limited to what the capabilities are.
- Muse easier to create sites but more difficult if you need something custom
- Dreamweaver more difficult to use but you have access to the code for customization
So it really comes down to what kind of sites you want to design.