If you use GoToMyPC and use the same username and password on other sites, hackers may have stolen your log-in info from one of those other sites and been able to log into GoToMyPC. There's no apparent indication that GoToMyPC has been hacked directly.
You should get a mandatory password reset notice at GoToMyPC next time you log in. So log in now and change your password.
And stop using the same username and password on multiple sites. emoticon.Wink.title