Just wanted to say this: HKDL is really tiny and if you go on the weekdays, there won't be a line more than 30 min (and you'll be hard pressed to find that). It is totally doable in a day.
If you're planning a return trip to Asia someday, you can skip it, but for someone doing a bigger, longer Asia trip and planning to hit Shanghai, HK and Tokyo, it can be done.
I have a job where I really can't take more than a week off at a time, so I'm used to shoehorning side trips in here and there. Or skipping them entirely, which is why we've had 2 trips to Japan and never gotten outside of Tokyo yet.