It is great that intranets are developing into something way bigger than “just” a communication media. They are supposed to be collaboration and cooperation platforms, interactive tools and an interface to legacy systems and business processes.
The last one makes a really big difference: this is were you get from talking to acting. That sounds as if communication was nothing (well, it’s my job, so dont get me wrong), but what I’m trying to tell is that usually communication sets the agenda and makes the decisions (things are determined a lot by the way they are told; think about new products, organizational changes, new managers) but in the case of representing business processes through the intranet, you learn a lot about the limited power of communication:
you have to understand the processes
you have to convince the process owners that they bother to explain the processes to you
you have to represent the processes in a way that others can also understand them
you have to create the communicative processes that surround the business processes; thats actually some kind of marketing activity
you have to question yourself if all this is actually worth it or if the world would not be much simpler and clearer if business processes stay where they are and intranets are communication media.
To keep it short: I definitely think that it is way smarter to combine things and make them visible via one source. The intranet should be something like a trademark – brought to you by your Intranet. It’s the first and single access point, and it provides all the information you need. Maybe not in all available depths, but it tells you were to go.