We all would like ATV to be a lot of things, but I think Apple a specific agenda on what they want it to be. Apple has made a lot of money in the media content industry by selling music on iTunes. I am sure they plan to try to duplicate their success in the Movie / TV market.
I have heard lots of ATV dream lists and here are my thoughts on what is possible and what is not.
Add a DVD/Blu-Ray player to Apple TV: I love the idea, but apple will never have it. It would be like asking apple to add a CD player to the original iPod. Apple wants you to buy and or rent from iTunes. Apple is ahead of the curve on being medialess. The Macbook Air has no drive. They have been promoting the .me service to upload photos and movies on to send to friends and family instead of burning DVD's. I think the lack of Blu-Ray in general from the Mac line up is solid proof that Apple wants to focus on the content.
PVR and/or Cable card slot: Never going to happen. Again, Apple basicly wants to have their iTunes become self serve online media company. What I mean by this is they want to be an alternative to Cable, Satilite or FTA TV broadcast. Instead of having to set your PVR to record 30 Rock @ 9:00pm, you set your ATV to dowload 30 Rock and watch at your convenience. iTunes only real challenge is trying to stream live events like news and sports.
eSata/external storage: Apple has never ( to my knowledge) sold a product that came with eSATA port. The posibility of exteral storage via USB may be a possibility, but I think Apples master plan is to have one Central iTunes computer in a home and your storage is expandable by how much HD space you have or by any NAS storage.
1080p HD sound: This has a very good possibility of happening sooner than later. With the new graphics cards Apple is adding to their line up, ATV should be able to handle 1080p. That being said, 1080p movies and TV shows would be HUGE files and take a long time to download. Sat and cable HD is only broadcast in 1080i. Apple might be in no rush to get to 1080p except to have the braging rights. Having 1080p too soon, might put too much pressure on them to provide 1080p content, which would provide most people with a very slow and frusterating movie experience.
If ATV does get any updates, it will be the following:
App Store: Very successful on the iPhone, would be a great entry point in trying to use ATV as a game console. Legal way for people to mod their ATV
Bluetooth: If people want to add a keyboard to their set up
SSD: This would give the ATV a bit quicker performance and run as hot
Bigger Processor: faster
iPhone intergration: Be able to choose a moive over your iPhone for your ATV to dowload. Movie or TV show is waiting for you on your ATV when you arrive home ready to watch.
Just my 2 cents.