Most consumer products (as opposed to some of those marketed to businesses) don't have enough of the components in place for the ME to accomplish anything, good or bad.
For starters, few consumer systems have the ME wired up to a supported Intel NIC to provide the remote access functionality that is usually seen as the scariest feature among those related to the ME. The processors are usually not vPro-enabled models so the firwmare will refuse to enable those features due to Intel's product segmentation strategy. And even if all the right hardware is in place, I think a system still needs to be provisioned by someone with physical access to turn on those features.
For most consumers, the main valid complaint about the ME is that it's a huge pile of unnecessary complexity operating at low levels of their system with minimal documentation. Anything fitting that description is a bit of a security risk, but the ME is merely one of many of those closed firmware blobs.
