I see two immediately obvious ways to offer a similar thing without the horrible.
One, a setting, subscribe me to comments on entries I have "liked". (This presumes a "like" that is an entryprop of some sort, rather than a poll; if it were a poll, I suppose one could have a subscription for "subscribe me to comments for entries that have polls that I have voted in", but that is really amazingly awkward-sounding.) This particular thing would be à la Facebook, but without the evil, and might possibly be a paid-only subscription, because it would result in a lot of notifications, similar to whole-community subscriptions.
Two, upon liking (or voting in a poll), offering subscription as part of the workflow. This would offer maximum control, but would likely lead to people overflowing their subscription limits quickly.
no subject
One, a setting, subscribe me to comments on entries I have "liked". (This presumes a "like" that is an entryprop of some sort, rather than a poll; if it were a poll, I suppose one could have a subscription for "subscribe me to comments for entries that have polls that I have voted in", but that is really amazingly awkward-sounding.) This particular thing would be à la Facebook, but without the evil, and might possibly be a paid-only subscription, because it would result in a lot of notifications, similar to whole-community subscriptions.
Two, upon liking (or voting in a poll), offering subscription as part of the workflow. This would offer maximum control, but would likely lead to people overflowing their subscription limits quickly.