Having applications that do one thing well is a key design feature for Linux. In my Ubuntu 10.04 LTS desktop I can scan through all my installed applications and choose the one I need for a task, or download an application if nothing is applicable.
Most times I use the major applications (Open Office, Lyx, Octave, Gimp etc) but lots of times I want a specialized application. I probably have close to a hundred separate applications on my machine. The point is that I want to browse through what I have because I can't remember all the names. Playing "where's Waldo" with my apps isn't my idea of progress.
How does Unity help me with daily productivity?