Win7 users: your thoughts on 'Voice recognition'?

With all the betrayal of trust by large conglomerates (like Goolge & NSA) what are the odds that if you 'train' your voice recognition application (ostensibly to control your computer) that 'voice pattern' won't be secretly moved to a data base, for use in some clandestine operation to spy on you, in the near future; and do you trust Microsoft with the ability to attach "backdoor" technology to accomplish same?