That's a good question since I don't pay much attention to it. I just note the size of my mpg and ac3 files, bring them all into one folder and if they're under 4 gigs I know I'll probably make it.

Then I do one prepare that lets me see how much space the VIDEO and AUDIO ts folders actually take up and bring in more if I need to or can. With Smart Prepare (which I just learned how to use effectively), adding or subtracting files and menus is no big deal since the whole project doesn't have to be re-rendered and you can quickly see if you've gone past the limit.

I then burn in Record Now Max (the old version) and it lets me know right away if I exceeded the DVD limit. (Never get to that point since I always know before hand, but it's one last warning if I forgot to check).

I don't think they made any substantial changes. Although DVDA 3 is a LOT better than the first two versions, this remains a rough edge.