Looks like the dell is using LG glass:
"Also going on sale Wednesday is Dell's 42-inch, enhanced-definition (ED) widescreen model, cosmetically identical to the HD set. The ED version carries a list price of $2,299 but is likely to be discounted to $1,999, considered the "magic" price point at which many consumers will happily open their wallets.
Both sets feature plasma panels sourced from LG Electronics, which is expected to offer its own $1,999, 42-inch ED widescreen TV next month under the Zenith brand name. And consummate shoppers may have already spotted a couple of other ED plasma options in the same price range."