I think when SL is finally released we'll see a torrent of complaints by people who don't understand what openCL and grand central are about. From reading this and other Apple forums it seems that a lot of people think their Macs will double in speed and that everything will be running on their GPU.
It's not gonna happen, they are developer APIs, things to make programming these technologies simpler, like Core Video, Core animation, Core Data, it will take time before programs are released that use them. The operating system and Apple supplied programs will be first of course, but I doubt they will have rewritten all of them and even if they did not all will benefit from it.
Take openCL for example, it can be compared to Altivec on steroids, great for large data sets and repetitive calculations, photoshop filters, simulations, quartz composer compositions, but not much use to Safari, Mail, iTunes, iChat and the like.
I'm excited about what will be done with SL, but you have to understand that it's not a magic wand that will make everything faster.