I would seriously consider this possible trend. If the Nvidia hybrid tech. takes off, ATI would mostly follow suit with their own if they haven't already. I know of one current/recent laptop which has an ATI/Intel HD hybrid chip but I don't know anything about it such as how it compares to Optimus and whether there is an inherent problem when it comes to Linux.
I am sympathetic to your open source demand but I tend to be practical of wanting it to 'just work.' FOSS is ideal but because of IP, patents, restrictions what have you, you know you won't have all features that the hardware can do. Unfortunately, with the market share of Windows being what it is, these manaufacturers test/design with Windows in mind. Not sure how to combat that or attract more attention to Linux but even the open source option has its limits. If market share is 1%, 5%. 10%, etc., you still have a small market and preaching FOSS is preaching to the quoir. Even if you convert a bunch of people, these companies are still going where the money is. For the big break through, I think you need some commercial push and then you have this ironic cunundrum that you probably don't even want.
Not sure what to do but I think when the company has no support solution whatsoever or it's barely usable or the main point of it is not usable in Linux, I cannot find any reason to support or recommend it (e.g. Nvidia Optimus). It's when the potential is there but not realized, and the reasoning is suspect, I have to object (ATI, ;-) ). Nvidia has the Nouveau option and although it apparently leaves a lot to be desired, it exists but Optimus seems to require a totally different function whereas in Windows, you can switch on the fly.
How does one deal with that? Market share it being what it is in Linux, you can choose to boycott or you can avoid it because the open source alternative is so poor. But, if AMD/ATI can't pick up the ball and run with it and has its own issues, coverting a few people to one side or the other does little. Another approach is needed and I, for one, have no idea what that is or needs to be.
But, I think Nvidia Optimus doesn't have a 'this method works' option so there is no reason to excuse or compromise with it. Not unless, you fold and go with Windows.