I agree. It's not a gamer word either. Derived from "the daily grind", it's just about lucrative but repetitive tasks. Sometimes they are fun but I also agree the connotation is that it is most likely boring unless specified otherwise.
Most of my gamer friends don't like grinding and usually stay away from "grindy" games.
Just because most people don't like it doesn't make it intrinsically unfun. If the above definition holds true no-one would like it except masochists. Anyway, as a counter-point RuneScape has a great grind with a huge player base and I know a lot of people who love grinding.
Is this actually true? The linked article doesn't say anything about it being fun or not. I love grinding and think it's fun in itself.