That's right. I hate it when people mess up the units like that. When I read that "X's GDP is $Y billion" with no mention of "year" or "annual" I am almost as annoyed as when journalists can't tell the difference between energy and power.

You're technically right, but I don't think I've ever seen GDP quoted as something other than per year, so there's no real ambiguity. The bigger problem is comparing GDP (a flow) to quantities that are stocks (total debt, market cap of X, etc.)

A slightly related problem is GDP vs GDP per capita, which during periods of high immigration or of otherwise rapid population growth can paint quite different pictures.