In it's current state (pow) Bitcoin can't be used as a (massively adopted) currency.
Don't think its a bad thing that Bitcoin is considered an investment (with some characteristics similar to gold).
In the end investors who are building up an portfolio will add all sorts of different assets to spread risks (ie. real estate, shares, bonds, commodities (silver, gold) and in that list in my opinion there will be room for bitcoin in the future.