If you're brewing extract, you really don't need to do anything different. If you're using it for all-grain, you will certainly want to proceed with pH meter in hand and prepare to adjust. The mineral content is all over the map depending on growing conditions, so the best bet is to adjust as you go.
Maple sap will contribute almost no flavor whatsoever. It will give a slight boost to gravity, maybe 1.005 - 1.015 depending on your sap. But hardly any flavor. Maple sap actually picks up a lemony flavor when fermented, which goes nicely in lighter beers and low gravity brews. Also goes well with earthy, floral, and herbal hops.
Sap should be slightly acidic, with mostly malic and some citric acid. The only significant mineral in it is calcium, with trace sodium and magnesium. I've seen maybe 25-75 ppm calcium referenced? No idea where that number originates, though.
A little later tonight I'll grab a pH measurement of fresh sap.