Had the keg been purged of O2 in the headspace (i.e. "burping" the keg)? If so, you should be ok.
If there is O2 in the keg and the beer is not carbonated, it may absorb or at least contact the O2, potentially causing problems.
Just get CO2 on it quick and drink it even more quickly.
perhaps a line of single hop IPA's - there's so many new hops out there!!!