New US booking site is nice, if you book a ticket ex-USA.
I think SK@AU booking site(which also uses Wideroe's booking engine. http://www.wideroe.no/sas/au/) is the best SK booking site for other bookings, including non-SK flights.

eg.
I made a booking of BX(Coast Air) between ARN-TRF on SK@AU site some weeks ago.
Incrediblly, it was the best price ever I could find for the same ticket.

When the same ticket costs me about 1300 SEK all-in through Swedish TAs, at Wideroe.no it was 700 NOK(ca 820SEK) all-in.
SK@AU offered 103 AUD(ca 570 SEK) all-in.

It was a paper ticket, but the paper ticket arrived 4 days after booking from Australia. I'm very impressed! ^