The following are the most current (known) firmware versions:
SIM-Free 1.15.405.4
UK
T-Mobile 1.15.110.11
Orange 1.15.61.10
Vodafone 1.15.161.4
O2
Three
Japan
Softbank 1.18.762.5
France
Orange 1.15.73.12
Australia
Telstra 1.15.841.14
If you can help update this list, please post your network, country and version.
SIM-Free 1.15.405.4
UK
T-Mobile 1.15.110.11
Orange 1.15.61.10
Vodafone 1.15.161.4
O2
Three
Japan
Softbank 1.18.762.5
France
Orange 1.15.73.12
Australia
Telstra 1.15.841.14
If you can help update this list, please post your network, country and version.