More than 1800 Minecraft user names and passwords were published online earlier this week, according to German publication Hesse, which in reality is almost entirely non-noteworthy as security breaches go; this is, after all, a game that recently broke the one million concurrent user mark. Even so, Mojang wants everyone to know that this is not a tip-of-the-iceberg situation—It hasn't actually been hacked—and also to remind its many players to be careful about how they handle their passwords.
Mojang's Owen Hill explained in a recent blog post that the accounts were compromised not by hackers, but as the result of [b]phishing scams[/b] by unnamed "bad people." [b]All compromised passwords have been reset[/b], and Mojang has sent out emails to everyone affected—and if you didn't receive such an email, then there's nothing to worry about.
Nothing to worry about unless you've been phished. Even then there's still nothing to worry about.
Remember, everyone: Never put your info down on a site that you don’t trust 100%. Even if it looks like it could be safe, you can never know! A common example of phishing like this would be the “steamcommuninity, etc.” scams where people give false links to steam that ask for your password. Just be careful, and ‘threats’ like this are never a problem!