If something is not illegal, as in added to the code of law, it is legal. For bitcoin to become illegal there would have to be established laws against it. If there are no such laws, it's completely legal, and since law doesn't work backwards, if it's ever outlawed, nobody will be able to prosecute you for using it in the past.
Also, it's worth mentioning that some countries already have laws that make bitcoin legal and protected by law, which means if somebody steals your coins you can go to the police, like you would have if they stole physical items.
Bitcoin status for some traders is always being blamed, but as long as bitcoin doesn't violate the law we don't need to be bothered, business people don't need to worry as long as the business can make us profitable and can be a source of income for us, then move forward while there is a chance, if our money is stolen we are indeed difficult to report to the authorities, but the case of bitcoin theft is very small, there is a case of fraud using bitcoin as a tool of evil is not theft.