Most likely because it is only supported on about 5 phones. Check out the Netflix site for the list of phones that are supported. But if you google for ' android netflix any phone ' that should point to a way to possible make it work. Brian
If it's not supported on your phone then it won't be in your market and right now the dx isn't on there line up but you can download the apk from this site and download the one that says Devise detection disabled and your good to go
It is in the market, but it will only show up if you're phone is currently one of the supported ones. There are many applications in the market that are device (or OS version) specific. They typically will only show up if the phone you're searching from is supported. Check out Tillyswilly's link to get it working without the market.