Too much lip service has been given to user or customer experience but little has actually been done to address it well. If you can be both, then you've really got it made. Both are important, and both are described in detail on our site. Our philosophy states that information is only created when care is given to the organization and presentation of data. Also important, which we don't necessarily lump into information architecture or design, is interaction design.
Most sites offer no real interaction despite the fact that they operate in an interactive medium.
What's often frustrating for clients is that there is actually a LOT of work to do before you get to see what it might look like. Clients often don't want to look at flowcharts and storyboards. They want to see pretty pictures that reflect what they'll be getting. It's become more integrated with other parts of the development process. One interesting thing about this medium is that, because the technology is so new and nonstandard, there is a LOT more teamwork required from a lot more people and this has to be closely coordinated.