DVD Dual layer compatibility ?
 

PC Magazine Sony DRU-700A
http://www.pcmag.com/article2/0,1759,1596432,00.asp

"We were further dismayed to find that DL media can't be read by any DVD recorder that isn't also designed to burn Double-Layer discs. According to Sony, this anomaly is caused by the fact that pre-DL rewriters don't recognize the on-disc media codes that identify recordable DL media; it's not a problem with read-only DVD-ROM drives or set-top players that lack recording capabilities. Manufacturers expect to release firmware upgrades that will resolve this problem eventually, but you may have to download and install them on affected single-layer recorders on a case-by-case basis."

AWWWWWWWW, that rots !

That only affects DVD burners, not DVD video players or DVD-ROM drives. So far we don't know any good compatibility results for DVD video and DVD-ROM drives. I haven't heard of any drive refusing to read DL discs though.

I'll probably get mine at Best Buy this weekend, so we'll find out soon.