Hi Vladimir,
I found a problem where if I have an existing link, say <a href=''>This is some test string</a> and I add a custom keyword 'is some' that points to some url, your plugin will try to rewrite the original link, even though it's already within the <a> tag.
The final text will be something like <a href=''>This </a><a href='whateverurl'>is some</a> test string.
The problem is not only that it rewrite part of the link - that would be undesirable but still working but the rest of the link - the string "test string" is now no longer linked at all - just text.
The problem currently manifests itself on this page, for example: http://www.androidpolice.com/2010/03/29/upgrade-your-android-phones-external-storage-with-a-data-turbo-16gb-class-6-microsd-card-review-and-benchmarks/
Here's a screen shot: http://i.imgur.com/lwTU1.png - "HTC Hero" is one of the keywords I added to the plugin. All text after it is no longer a link.
Thank you for looking into it and feel free to contact me any time