At this point, it was Thor's decision exactly how much frostbite he wanted to inflict on himself. Loki was content to let Thor make that decision - though he would intervene, probably, if it actually looked like the man intended to sacrifice a hand - and building up the ice sticking his feet to the roof wasn't taking as much concentration as he'd thought it might.

All of that meant that Loki had spare mental space to think, which generally meant he had space to talk. This time was no exception, though he made an effort to find a topic he thought would please his brother. "Have you decided what to do about the sword thing, at your wedding? Since an ancestral blade of your fathers is likely to be... difficult... to come by."