Quote:
Can any device that accepts CompactFlash use any capacity of CompactFlash card?


No. Some cameras can only handle a FAT16 file system, you need one that can do FAT32 to handle more than 2GB.

http://www.digitalfilm.com/pdf/Lexar_4GB_Fat32.pdf

There are also two physical sizes, type I and type II.

Quote:
Can any device that accepts CompactFlash use any capacity of CompactFlash card? For instance, if you owned an older camera that was made back when CF cards were a maximum of 256, would a 1gig card work in it?


Probably. Most CF cards are type I and a camera that can cope with 256MB should be ok with 1GB.
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