That means a DVD+RW can be written to without gaps, just like you can write to a floppy or HD with accuracy in the written sector/without gaps.

And this in turn means that only DVD+RW supports Mount Rainier (in the future). Mount Rainier is hardware assisted packet writing:
- The most important thing is that you can use your DVD+MRW (Mount Rainier Rewritable) as a floppy disk/Hard drive. You drag and drop, delete, write something else etc. Just like a storage device is supposed to be used, none of this "burning" crap. MR has extra fault tolerance too.
- Standard OS drivers for all MR drives, they all behave the same.
- Formatting in the background by the firmware, the RW can be written to after about 1 minute, you don't have to wait for the whole DVD to finish formatting to start using it.

Only problem is, there are no fully compliant Mount Rainier DVD+MRW drives yet :(
The manufacturers are now scampering to get to 16x speed first. After the makers all achieve 16x then we'll get get other differentiating features in the drives, like MR.

The only advantage you get with +RW at the moment is that OTHER packet writing methods (like Nero InCD) also benefit from the exact laser positioning. You don't get Some of the other MRW stuff like background formatting.

I'm waiting with buying a DVD drive until there's an +MRW. You can also recognize compliant drives with the Philips "Easy Write" logo.

P.S. the DVD-R and -RW camp are the ones that do whatever the movie industry wants. The computer manufacturers split from that group because they wanted better features like absolute write-positioning and came up with +RW.