I’d say, the keyword in tracker learning is “enthusiasm”: it’s surely a challenge to learn if you already are accustomed to other kind of interfaces, but if the tracker interface tells something to you, if you hear a “siren voice” calling you from the rear of the monitor when you look at the pattern editor, then you will definitely not waste time learning it.
crytek is right: Renoise is definitely not for everyone and, although our aim is of course to widen our user base embracing people who never saw a tracker before, we cannot convince people who are willing to create music in no time with their mice (the hardware ones, I mean 
).
so, welcome aboard, feel free to ask for help about anything doesn’t look clear to you, check the beginner’s introduction and give this monster a go!