i think its hard to answer because there is no architecture market which can be described as one thing.
to answer your question depends from which market your work is coming from. i dont care much about these houses because i havent shot any of this kind of buildings before too.
for sure the houses stuff will decrease , allthough we in germany havent had this market similar than in the US. in Spain they have build 1.000.000 unnessesary houses too, but i even doubt that anybody needed good done architecture photographs from this speculative and c***f** houses ( thats how they mostly look there and many many are even empty,- you shoot one of them and you have enough to sell the other 1000000 all over the country, cause one looks as the next ). i have to admit even to hate them since several years lot for ruining some of the best and loveliest landscapes in Spain for nothing except to drive the prices of all other houses in crazy hights and to make some, few people rich .... so probably i never was the right photographer for them, also i nearly never saw good photographs of this kind of houses, i think the investors would done the hell but invest in good photographers,- the houses sold from alone because the buyers believed to double their investment in at least 3 years. than came the end of the price and house flood and it came so fast that no one tried to sell better with good photographs because it was obvious that nothing was going anymore. at least the next 5 years, but i believe that many of the empty houses will end up as nice ruins. than i will photograph them
bigger architecture projets are normally longer term plannings so they wont be affected so rapidly, same about museums, public projects and so on. public projects even might increase cause several governments will try to help in spending more money in constructions- ( although some government dont want to show in bad times that they spend "unnessecary" money in expensive looking publications for not beeing criticezed to waiste taxes ... . ). i have some investment fonds as clients who invest in ( large ) estates, which seem to spend very carefull money at the moment, but i wouldnt make a rule out of it.
myself i am usually busy on several tracks and i still dont have a clear idea how the crisis will affect my commercial work or not, at the moment i dont feel it, but as i said, i am busy on different tracks ( art, architecture, museum) so it could come little bit delayd to me if the things run bad. honetly i am more concerned about a real big financial crash in the near future ( which would mean that we just see the introduction of the big bang at this moment ), but lets hope. and after this crisis has passed lets hope even much more for our ecological envorinment and future,- honestly this makes me much more fear for me and my children.
im general i see that much more people want to come in architecture photography than some years before, i think mainly because its cheaper and much more easy to do with 35mm cameras smaller jobs than formerly in the film days. this has a deep and fundamental impact as i think, because its ( probably ) much more diffficult to come in commercial business than some years ago, cause 100 times more photographs are been taken of each project and "cheap" clients often will be satisfied with "cheap" images,- which simply werent available so much in the pre-digital times.
i am shooting at the moment a new museum in munich which is looking spectacular. you cant imagine how many people come and take shots. maybee 50 persons take their shots at home each day ...
its really funny but serious too, allthough i dont see that this might affect my work this months, in general the availabilty of "gratis" shots will have a big indirect impact for the whole photo world,-
probably more than the slow economy ever could have.