It’s tiresome and bland. “For the win” may be the Internet generation’s “swell”, “radical” or “dope”, but like those words used to be in their respective periods, this phrase is trite and devoid of meaning. If you cherish language, or, at the least, want to use your language to make a lasting impact on people, wean yourself off this phrase. It doesn’t have any significant meaning that “great” couldn’t convey, and only serves to weakly identify you as someone who jumped (likely late) onto the bandwagon of contemporary Internet culture.
I guess you can say it ironically, though it’d be hard to pull that off in the current climate. I suspect one day “for the win” might have a kind of retro-cool about it, like “gnarly”, which will make it permissible as it will serve as an indicator of what kind of person you are, but for now, it’s so divested of any meaning that you may as well just say “great”, “excellent” or “outstanding” and avoid looking like you’re trying to attach yourself to a culture you’re not a part of.
Please, link others here. You may also peruse the other words and phrases nobody should say or ruin.
Disputes and suggestions may be directed to SuitCase (Email link).