I think you are exactly right about the potential of the computer as a distraction. In the "old days", you could go check the physical mailbox or the answering machine or the weather in the newspaper ... but these things weren't continually updating in the same that blogs and email and news web sites update.

Someone said above that Google and Wikipedia make them faster, which it no doubt does. Google Books has expanded my ability to do research, allowing me to preview and search books that I could then find at libraries near me. It just requires a lot more discipline to stay focused, I think.