the reason the MBA is "so amazing" is only partially the SSD drive. it's the form factor, the weight, and the build quality. the build quality will be there with all Apple products, so it's the size and weight that are your deciding factors.
the MBA will always exist and sell very well because the performance gains from the SSD drive will benefit most "average joe" and "medium" users. it's a much better speed upgrade over just a processor upgrade.
however, the MBA will still be limited by the following:
- anyone doing video editing, audio editing, or intense graphic work will likely need both firewire and a fast processor.
- anyone needing to do rendering, hardcore gaming, lots of video conversion/compression (such as with Handbrake), or anything else that mainly takes its hit on the processor or requires a top-tier GPU.
- anyone who regularly works with CDs and/or DVDs or needs to be able to burn them.
the MBA will not shine in these areas, and if you foresee yourself doing ANY of this at least once a week, get the MBP.
that being said, the MBA will be *perfect* for: web surfing, email, research, homework, light gaming, software development, light photoshop work, and almost any other "every day normal" task you throw at it, and it will still get by at the tougher stuff, albeit more slowly.
now, with all that out of the way:
new MBPs are hard to predict. i do think they will gain some sort of onboard SSD/flash option, and will have the option to have either a superdrive or a second hard drive for storage. they may also get marginal cpu and gpu upgrades, and a slight styling buff.
however, if you need to do CPU-intensive things but are lusting after the SSD speeds of MBA, know that you can install your own SSD into a MBP fairly easily, and you can even install a second hard drive in place of the optical drive if you don't deal with CDs and DVDs.
so to answer your questions: no, the MBA will not become any less amazing. yes, the MBPs are moving towards SSD boot drive options, no, I don't know when it will actually be put in place, but no, nothing is stopping you from ordering a MBP now and adding the SSD yourself.