A light wipe with glass cleaner in a rag should take off just finger prints pretty well. It leaves no protective film though.
I like the Clorox handy wipes for that type of thing. Although I do my keys mostly with that and pretty often, since kids are at them with who knows what germs. I hit the fall board while I'm at it. My grand is satin black as well. These are the same ones you might do your counter tops with. They are sanitizers as well.
Also, another good product for the finished wood surfaces only ( don't get this on the keys or you will slip and slide all over them) in general is Pledge furniture polish in spray, we use Lemon Pledge. I build clocks, actually clock cases. The clocks are finished in either lacquer or shellac and the pledge works great on them as a general clean and brighten up product, removing fingerprints and dust. I've used it on the piano top many times over the years. It will raise the luster a little bit when first done.
Topic: Satin-finished Yamaha Upright