I class data transfer speeds as essential information when buying any memory card. Therefore EVERY card should have the speeds in the technical information section of the product description.
Browsing the today only page I saw a number of SD cards, most with speeds listed. However a few products don't, example:
http://www.scan.co.uk/product.aspx?ProductId=23896
Sort it out scan, how is someone supposed to decide if this is a good value product with such pathetic technical information?