We have removed a number of merchants from ECU today as they are closing their programs on the relevant networks.  You need do nothing about this as the products will be removed from your units.  If however you have opted to show out of stock items, you will need to manually remove them from your units using the tool on the My Merchants page.

The merchants removed are as follows:

Graham & Green (via Linkshare and Affiliate Window)
Genie Gadgets (via Paid on Results)
Perfumes UK (via Paid on Results)
Advanced MP3 Players (via Paid on Results)
Clip Hair (via Webgains)
Rivetonline (via Webgains)

Remember you only need do anything if your units are set to show the missing products anyway.