My own, brief take is that content management has to face a number of challenging questions over the next couple of years.

Will content need to be managed?
Content management currently focuses on providing tools for groups to create, review and retrieve content so that an approved version of that content can be made available to predefined audiences. User-generated content and the broadcast models of social networking challenge that focus.

1. Anyone can view content: most tweets go to everyone rather than direct to individuals.
2. Anyone can contribute content in a UGC world.
3. Distinguishing what’s your organisation’s content and what’s individual is becoming increasingly fraught; just take a look at any blogger’s site for disclaimers even though they’re blogging about their company’s services.

Will content need context?
Even in the least structured repositories (wikis, flickr, twitter) content is still tagged so that it can be retrieved. But the onus is on the user to find the right tag and on a search application to enable this. This is quite different from a CMS, where the software provides contextual models like folders and related documents to guide the user through an information architecture. As search interfaces and technology improves, there will be less need to provide those contextual models. I have my doubts that semantic mark-up will help people create more relevant content, but I do think that improvements to search will mean that content will be “find-able” and “relate-able” anywhere, even if it isn’t in the right taxonomical folder.

Will content need to be deleted?
As volumes of content continues to increase and contextualisation decreases, finding relevant content amid all the dross will become harder. I think that this will be an even bigger business driver than cost of storage for deleting content that’s irrelevant. But because distinguishing “approved” and strategic content will be harder, it will also be hard to identify which content is dross and what might be useful. Socially-driven records management is bound to take a stab at this problem, but whichever content management tool can help people to get rid of useless content is going to be a winner in the long term.

Firstly, by providing a simple search box. After all, this is the way most people find new information through Google. Secondly, by using a search tool to push similar content to users; for example the right-hand column of this page provides links to pages that are classified under different themes. But before you view search as some kind of panacea for all your information architecture woes, let’s pause to reconsider these two methods.

In the first case, how do you know that the search results presented by Google are the most relevant pages to your query? Google has no real benchmark. Then weigh up how much effort people put into ensuring their content is optimised to appear at the top of the search results and then ask yourself what you’d have to do to ensure that relevant content for every search a user undertakes.

In the second case, consider that actually I’ve already (very loosely) made decisions about navigation by tagging every post. This is almost the same effort as organising the content into folder structures as you would in a CMS. In fact, for sites with lots of content it can be more difficult to tag all the content than to drop it into a folder structure; the folders provide a more complete classification metaphor that’s easier for people with less expert knowledge to implement.
So how do you decide when search is better for navigation than in a CMS? Here are my suggested criteria:

1. You have the money.
   Implementing faceted search technologies can be significantly more expensive than using standard content management system functionality. Day rates for leading product professional services are often relatively high, there are licence costs and there’s an additional cost of integration, particularly if you need to tie a security model into the search tool.
2. You have few content types.
   But you have lots of content. Structured navigation from search works well where you have similar kinds of content, with similar structures against which the search engine can execute straightforward queries. A product catalogue is an obvious example. The tool can filter on price, format, location, etc. which have definitive and distinct values.
3. Your content is distinct.
   Categories need to be unique; semantic tools aren’t really advanced enough yet to tell you that apple is a fruit not an iPhone when displayed with orange unless orange is the network provider. Moreover, your pages need to be called something readily identifiable. If you have ten pages called “Help” or “Contact Us”, how will the search tool know which is the relevant resource for the site visitor?
4. Linking is obvious.
   If you use search to provide your navigation, you relinquish editorial control, so it must be clear why pages in the navigation are related. On a medical site, for example, you might link to other conditions treated with the same drug. However, as soon as you’re trying to tell people something you can get in trouble if you automate. An example I often use is a page about health advice for eggs: should this link to information about required protein intake (i.e. eggs are good for you) or about cholesterol (i.e. eggs are bad for you)? Or should you exercise some editorial discretion and explain about balanced diets? There are few search engines that could perform the navigation required to achieve the latter example.

Practically, it’s generally simpler to use CMS to navigate, with a search option to help people who are stuck. The advantage of CMS-driven navigation is that the editorial control you can exercise should help you to push visitors to your site along a route you want them to take. However, if you’re happy to let your intrepid visitors explore your content, and you’ve nothing in particular you want to promote to them, then search engines can be a viable means to provide navigation.

My final analogy is that CMS-driven navigation is like a library, while search-driven navigation is more like a bookstore. In a library you’ve preplanned how visitors can find specific information. In a bookstore you’re encouraging them to browse, but they may never find what they came in for.