I experienced several problems with the Icelandair website over the Easter holiday weekend. I actually found an amazing fare from YHZ to LHR return on Easter Friday, but their "Iceland Stopover" function on their Canadian website did not work. I sent them a message but to no avail. They refused to give me the fare (that had gone up by Tuesday) although they did acknowledge that their site did not work well. I have know booked the ticket though my travel agency.
On another note, does Icelandair have a seat map of their 757 on their website?