Re #2: I'm also curious about how you go about deciding what UI elements should be on the page. When I sit down to design a UI, I have the hardest time deciding on what blocks to plop down. Should 'this' be a button or a link, or should 'that' be emphasized or de-emphasized? Do I even need this element on the page? I usually feel like I'm so far off on these large scale questions that the finer points you describe aren't worth worrying about yet.
Any chance of a second UI ebook dedicated to these (trivial to experts, I'm sure) concepts? I'm a developer at heart, not a designer. Design doesn't come easy.
P.S. Some months ago I deleted my account with Paypal for moral reasons. When I tried to put in my credit card info, Paypal recognized my card as belonging to a deleted account and refused to accept my payment. Grrrrr.
I agree - I'm not sure whether to call what I find most challenging "Interaction Design" or "User Experience," but there are a lot of elements of design that are neither technical nor aesthetic. In the chatroom example, there isn't much involved because it appears to be so generic, but as you innovate more and more, this ID/UX becomes increasingly challenging.
One slightly related design problem would be, for example, how the buddy list on facebook chat works. One could classify users into groups, allow you to 'pin' a user at the top, expose more ways to have group conversations. While, one could always argue for the simplest possible solution (i.e. one big list!), it's not always the best for the user and I would read anything that helps in guiding processes to discover and decide what is best for the user. In my experience, good UI is often far less controversial than good ID/UX and less of an issue when keeping a team happy and excited about a product. All of the biggest issues where I work have been on a much bigger paradigmatic level that we debate on philosophical grounds endlessly to little avail.
Totally agree, for me the hardest part is the kickoff where you have an idea in your head and need to visualize it on paper before actually starting designing the UI. I would definitely pay for another e-book that handles the conceptual phase of an interface/application!