anybody know if this is particularly rare?

[edd_jedi]

i was amazed how much this went for yesterday:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&item=300045514274

i can't say i've seen many 48 backs around, but this is more than the 31 back goes for! is it just a lucky auction for the seller?