Though many people who use SpyBot Search & Destroy in conjuction with their other security programs are aware that it does not automatically update (same with AdAware), some just ignore it. Today I found that there is a realitively large 'Detection Rules' one available (1.7Mb) so am just pointing this out to folks. Just open program and hit 'search for updates', then download.
A small note on the message '!!!bad checksum!' , it just means that that particular server is overloaded, simply go to the dropdown menu to the right of "Search for Updates" and choose a different mirror site, ie 'Safer Networking #2 (Europe), and click the download button again.

You bring up a good point this doesnt realy effect me as I already knew about the updates but some users may not ! I like to manualy update all my software as sometimes the updates are buggy (usualy your safe with detection rules)