How can I use a keyboard shortcut to go to my Dropbox folder
System Preferences > Keyboard > Keyboard Shortcuts > select Application Shortcuts in the left column > click the "+" button > Application = Finder, Menu Title = Dropbox, Keyboard Shortcut = whatever you like > click Add

test it out. worked great for me from Finder

Note that this uses the Finder's "Go to > Recent Folders" Submenu. If the Folder isn´t in the List (and there's no way to keep it there), you won't be able to jump to it.