Both buildings have been given odds of just 5/2 to win the coveted award, a move which has surprised some critics, who touted the much-fancied Scottish Parliament building as the early frontrunner after the shortlist was announced yesterday.
However, William Hill is offering punters odds of 5/1 on RMJM and Enric Miralles' controversial Edinburgh project - the same as Zaha Hadid's universally praised BMW Central Building in Leipzig.
Meanwhile, it will not come as a shock that Will Alsop's Fawood Children's Centre has been made the rank outsider at a lowly 7/1.
Some observers felt the scheme in Harlesden, north London, was lucky even to make it onto the shortlist.
But those wanting to have a flutter may want to take a look at O'Donnell + Tuomey's Lewis Glucksman Gallery in Cork.
The Irish scheme offers excellent odds at 7/2 and has already been touted as the dark horse on the list by some of architecture's leading lights, including Richard Murphy.
Sponsored by The Architects' Journal, the winner will be announced at an awards night in Benson and Forsyth's National Museum of Scotland extension in Edinburgh on 15 October.