I checked with one of our marketing gurus who checked various sites, asked service and spoke with several other knowledgable people on this issue. Apparently, one of the ads had a typo - there is no R1.
Both units should be a D1.
I hope that helps.
Vanns has the Samsung LN46A950D1FXZA for $2,499.99.
Electrozone has the Samsung LN46A950 for $2,449. and the Samsung LN46A950R1FXZA for $2,899.
Calls to Samsung, Vanns, and Electrozone haven't totally clarified the differences. Electrozone has indicated that the Samsung LN46A950R1FXZA has a dcdi chip but the Samsung LN46A950 does not. Is the Electrozone Samsung LN46A950 the same as the Vanns Samsung LN46A950D1FXZA, making the dcdi chip a $450 option? Is it worth it? Is it even true? Even Samsung level 2 tech support doesn't understand the model number differences and don't know any thing about a dcdi chip. Can someone comment in this forum with an answer?