This is for the 16GB card, works out little cheaper than the 8GB posted here.
16GB is usefull for recording videos, on many of the new devices. an advantage with DSLR's like canon 550D and 60D, where files tend to be very large.
less swaping of cards - also the 32GB is £39.99 little more expensive per GB
Fully compatible with SD 2.0 Standards, SDHC Class 10 compliant, Compatible with all SDHC-labeled host devices
Built-in Error Correcting Code (ECC), In System Programming (ISP)
Secure Digital Music Initiative (SDMI),Content Protection for Recordable Media (CPRM)
Auto-standby, Power-off and Sleep modes
Mechanical Write-Protection Switch