You can cite industry improvements in the manufacturing process that companies say will effect the price at a certain point along with scientific developments and in general claims made by actual corporations.
I mean you can cite predictions but unless there is trend data to back them up I'm not exactly sure how useful they are.
I think wmf is looking for citations of things like trend data and maybe even plans from SSD manufacturers that shows "hey we're working on this cool tech that should help us lower costs by next year!" types of things.
