This app is great for those of us that monitor a variety of systems. I don't actually use it to monitor my personal OS X logs, but rather I run it on my OS X box in Monitor Mode to watch logs on a variety of other systems, including SQL servers, mailservers, FileMaker Servers, and OS X Servers, emailing my staff and I when there are problems.

There were a few interface features that were missing, but the author has been correcting this over time and the interface is complete and usable, if still a little quirky to figure out. It could still stand to do a little more auto-refresh for User Logs as they're selected, though.

The author is very responsive to suggestions and bug reports; I suggested drag-and-drop functionality about a month ago and it showed up today in v4.2. I haven't seen any of the stability issues mentioned by the other reviewers; it hasn't crashed in over two months of 24/7 use, monitoring logs on mounted shares.

Overall, a valuable app that performs a necessary task for us automatically, and there doesn't seem to be anything like it either for the Mac or even for Windows. Along with WhistleBlower, this app forms one of the cornerstones of our automatic fault-detection system.