I wanted to qoute this because they worded it better and it will be clear so the questions about it will stop.
4gb and 8gb Memory Stick Pro DUO
Posted by Ian13 PSP-Hacks.com
Sony has updated their MemoryStick Website to include their latest product unveiling at the International Consumer Electronics Show (CES) in Las Vegas. Touting the way of “Gigabyte Life” as their theme, Sony announced that they plan to release 4GB and 8GB Memory Stick Pro Duo’s sometime in 2006. There is no mention of price range at the moment, but you can bet it’ll be pretty pricey at first.
The PSP doesn’t currently support any storage media exceeding 4GB, so you can expect a firmware update to be released at about the same time as these new memory sticks to accommodate for the massive storage if Sony wants PSP users to snatch up the 8GB version.
Please look at the part in bold&underlined. The same thing goes with the converter. If the PSP can't read msduo > 4GB then it cant read CF/MD/SD/MMC >4GB untill the new duo's
AND most importantly the new firmware