Here's the scoop: if there's an "s," don't use "less." There are a few exceptions to that general rule (like feet, a plural without an 's'). But without exception, countable things need "fewer." If the noun is not countable/counted, then "less" is correct.
Oprah has less time to herself these days now that she's launching a network. // Oprah has fewer friends these days now that she's launching a network.