Is it still necessary to fill in gaps in sequence? I know that in the early versions of PremierePro it was necessary to fill all gaps in your sequence (places where there was no video) with black video.
If you left these gaps Premiere would give you trouble exporting or wouldn't export at all. Does anybody know if there is any need to still do that, or is that a thing of the past?
I don't think it has been an issue for some time.  I've been using Premiere since version 5 and don't seem to recall ever having a problem with exports though I don't recall my work area ever extending over a gap (though I certainly had many projects where there were gaps between work areas.)

I did verify that in CS6, it is no problem.