An example of the progress of the modern web
I've recently wound up being in the (Toronto) real estate market, which has given me an interesting opportunity to see both how much the modern web has changed the world (okay, the way things are done), and how much further it still could go.
(Usually I don't have much exposure to ordinary commercial websites unless I'm looking for something; it's only then that I get to experience the full joys and annoyances of dealing with whatever companies have decided is theoretically useful today.)
On the changed the world front: I've been doing much of my searching through realtor.ca, which is run by the Canadian realtors association and has a powerful set of tools for both filtering things for sale and seeing where they are. I really don't want to think about what this process would have been like even, say, five years ago, much less before the web had caught on at all. Realtor.ca is very clearly a creation of the modern web, the whole environment where it's possible to do complex, highly interactive 'website as application' sites with fluidly interactive elements, information popups, and so on. Even a five years ago version of this would have been much simpler, much less interactive, and much less useful, partly because I think it wouldn't have had mapping; my perception is that the whole interactive mapping boom on websites is ultimately due to Google Maps, which had only just launched five years ago.
(I suspect that this is both positive and negative for realtors. On the one hand, this must result in much less time wasted in their office with prospective buyers and a big map, sorting through piles of listings; on the other hand, knowing listings and locating things presumably used to be part of their specialized expertise and value.)
At the same time, there's a lot of ways that the whole experience could still be improved, some of them illustrated by Zillow's interface (sadly Zillow is not available for Canada). For example, imagine what you could do with analytics on real estate data; given a bunch of selling prices for a bunch of properties with various features, you should be able to work out things like what on average a certain amount of money gets you in various neighborhoods, or how much more (or less) a given set of features will cost you in different areas of the city (essentially giving you neighborhood price differentials). Once you have the information, there's lots of interesting mapping visualizations you could provide on top.
(You could also go on to suggest an answer to everyone's hot question of whether or not a particular listing is probably overpriced (or even underpriced), or what a particular house is probably worth. Also, Toronto at least used to be infamous for properties being deliberately underpriced in order to induce bidding wars between prospective buyers. I don't know if this is still going on here, but you could easily spot this by comparing listing prices with sales prices, and give people clear indications of what areas this was happening in, or alternately what areas people were overpricing things in.)
Normally I would say that there are clearly some opportunities for startups here, but unfortunately all of this dreaming points to a problem with doing more sophisticated and engaging web interfaces for this sort of stuff in today's world: access to data. In order to build a website that offers a better real estate experience, you really need the realtor.ca data and that data is not freely available; it's owned and controlled by the realtors and their trade associations. I can't imagine that they're is interested in either another competing website or in adding features to their own website that seem likely to make realtors even less necessary than before.
(From that perspective, I'm honestly surprised that realtor.ca offers as much as it does, and I'm amazed at Zillow's apparent ability to get the equivalent data in the US.)
PS: it appears that actual sales information is public information in Canada, although it's not online as far as I can see. However, listing information, probably including all of the property features that realtor.ca tracks, is owned by realtors et al.