Apparently - all DVD players in PAL countries can play PAL & NTSC encoded discs.
http://www.dvddemystified.com/dvdfaq.html#1.19
Also apparently - some companies have DVDs that take advantage of the slightly better resolution of PAL.
http://www.amazon.com/exec/obidos/su...no-links.html/
So lazy cost effiecient companies - not concerned with regions - will make only 1 version - the NTSC - as it will play on all DVDs and they can just package it differently.
Some comanies that care more about quality (or are trying to perhaps get the videophile market) in PAL countries will make both versions.
So it is sort of like Super VHS - except not as big of a difference. Most SuperVHS players will play regular VHS, so most will only make the regular version.