After you've uploaded via PAUSE, the distribution will be indexed within a few minutes, and will propagate to the various CPAN mirrors within a matter of hours. I suppose it's possible that some of the stragglers might take a little longer, but I generally see new releases reflected in the mirrors that I'm using after a time period on the order of 2 to 4 hours.
This doesn't have any impact on the ability to install your module, but might be of interest as an aside. When things are running smoothly, it can take about a day before the smoke test results start making their way onto cpantesters.org. And once that's happened, it takes about another day for your CPAN listing to begin showing a tally of PASS/FAILs.