FI back in October announced that they plan to offer a extra weekly flight and a improved schedule on it's LGW
service from 14MAY13 . The 3 x weekly service will offer more connection opportunities for passengers wishing to fly between the UK and North America compared to the current W12 schedule.
11:15 757 4
19:45 757 7
15:30 757 4
23:55 757 7
11:45 757 247
15:10 757 247
Personally i think the timings of the Icelandair flights from LGW
during W12 are perfect for passengers wishing to visit Iceland for a long weekend but are not great for those wishing to connect to the carriers services to North America.