Yes. One USD buys 7.75 HKD (roughly - there is a small band). At the moment one USD buys 6.24 RMB, so I'm guessing that if the peg breaks, that would be at least the initial place for the HKD to go to.
Could be a lot higher, mind you.
Instant pay rise (at least for those repatriating some portion of your pay) for HKG based people?