Just did some more research on this. Its not just rolling code openers. There are a slew of new openers that won't work with homelink without buying an adapter ($70 - its the first thing listed under FAQ, so it is becoming a big issue). If I look at this from a business perspective, I would have to ask myself:
1. How much does it cost me to install homelink?
2. How many owners use homelink for anything other than opening the garage door?
3. Can a home owner buy homelink functionality?
4. Which decision will create more negative feelings:
a. Not installing homelink
b. Installing homelink knowing that its not going to work with several popular brands of new garage door openers and people are going to have to pony up money for adapters
If I'm GM, I'm trying to cut costs and create a positive customer experience. IMHO, the uproar in this forum would be far greater if homelink didn't work than if it wasn't there. Yes, people aren't happy its not there (me included), but I would have been far unhappier if the buttons were there but they weren't usable with the new garage door opener I bought (I'm glad my research led me to the adapter - it will make my wife very happy that she's able to use her homelink again).
In my case, I found a very small remote that is compatible with my garage door. I'm able to tuck it out of the way, it does more than homelink, and I didn't end up paying for it and homelink (you don't think that GM wouldn't pass the cost on to me).
Having said all of this, I believe it would have been in GMs best interest to point out that they weren't including it and tell us why. I'd rather hear it from them than to try and speculate.