An easy way to check for sure whether or not its DVD5 or DVD9, is to just pop it in your DVD-ROM drive, and look at the size. If its greater than 4.7GB it definitely is a DVD9 (dual layer).
...anyway not to get too off topic. Ady, I am really looking forward to your DVDs, and am gonna grab both the DVD5 and DVD9 versions once they are out. Thank you so much again.