I first encountered Katherine at Wet Canvas at the Coloured Pencil Channel and found her later at her current blogs.
At the moment, Ms. Tyrrell is collecting nominations for best in several areas of blog-land and asking for recommendations. I haven't found myself able to come up with a worthy nomination, not because they don't exist, but rather because Katherine has such a great handle on what happens on the web. It always seems that Ms. Tyrrell is capable of circling the entire web and finding its artistic pulse.
If you don't read Making a Mark, today may be the day to begin with her weekly column on "Who's Making a Mark this Week. It is a post I eagerly await.