Can this be abused? Yes. Read this thread at TL.net forums of how Malmis describes how some one owned him with this bug » Malmis owned and watch this » replay of another example that shows the abuse of this bug with perfection. Bottom line, if Zerg does not place an early sunken before second hatch, or go early pool, with this bug Zerg is doomed to suffer and be at the mercy of the stack SCV rush.
This is not strictly a bug, since it follows all the original micro AI intent of the units involved. I suspect this bug is much older than we give it credit. I think it has simply has been discovered rather late but that it is possible even with 1.09 patch.
Links
Broodwar.nm.ru - Source
Tl.net - Source
Sg.com - Replay