Hi Yoshi, yes I suspect that until prices come down the attraction of an SSD to upgrade a laptop that does not have a secondary hard drive will be hard to justify.
But I think an SSD for a desktop makes a lot of sense. I think a 64GB SSD would be adequate for a desktop as it would only need to contain program installations and the OS. My own installation with big suites and many other programs installed only totalled 30GB. The speed benefit if placing programs and the OS on an SSD is well documented. A 64GB SATA III SSD is around £75, so although per GB not very competitive, it's still an affordable upgrade. You can now also get disk cache SSDs. These work to speed up conventional hard disks through intelligent caching via SSD. I have read positive things about these too. So you could eventually have one SSD for the OS and programs, and another SSD to accelerate your conventional hard drive.