The phrase "faster downloads" means that files or information can be transferred from the internet or another source to your device more quickly. Full definition
Enjoy improved performance that allows for faster download speeds and software loading times. (nintendo.co.uk)
Number 4 is only for faster download speeds, graphics being enhanced isn't confirmed at all. (n4g.com)
This new 3DS will also boast a better CPU (which will provide owners with faster download speeds and improved web browsing / streaming activities) and an improved 3D display. (heavy.com)