Memory Stick Micro M2 memory cards : 1GB, 2GB, 4GB, 8GB Micro M2 memory for the latest Sony Ericsson mobile phones like K800, W880, W770, K810, T650 and others. Get the biggest M2 cards at lowest prices.
Remember it starts with "Sony"
I am sure it will work in the w580i as it works in other brands with the exact same software on the phone.
I just bought one now ;)