I like this little application quite a lot. The basic functionality works very well and is very useful for gathering this kind of information. Exporting to .csv is great for saving out those times for later.
However, I see a lot of room for improvement here, if the author is willing to put in a little more work.
For one. I would love to see some sort of exclusion function. For example, it would be nice to be able to say, exclude Finder, or maybe some other applications from being captured. We really don't need to see how long we spent in certain applications. But make it a user set preference on what to include and it'll be great.
Also, why does the app capture itself in the timers? That seems silly. Why would I care how long I spent in the preferences of the application, or in the main window? It just clutters up the view.

Also, it would be great if we could export only apps that we select, rather than the whole shebang. This function may not be necessary if we could exclude apps from being captured (point one above)

Lastly, someone commented on making it a menu item, at least as an option. I think that would be good too, if it's possible to do with this kind of application.

If the developer could do these things, I think I could even convince my company to buy licenses of it, even though it's currently offered for free. We've been looking for something that can do this, and this comes close, but is not quite close enough for us to pay for it yet.