I say fill it all the way up and bring me my damn burger already. What kind of crappy service is this?
(Or, the glass is simply twice as large as it needs to be. Or both half full and half empty at the same time. There are a lot of answers one can use here.)
Really, I think it depends on what's in it. If it's egg nog, it's half empty. If it's something gross, it's half full.

(Or vice-versa. Actually, whether it's that way or vice-versa really depends on... WHOA)
Also, amusing bit of perspective: Often are glasses completely empty, but rarely are they completely full. Think about that...
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