The Flickr Group Tracker allows you to highlight threads in Flickr group discussions. Here's a screenshot of a sample group:
Topics you post in are automatically highlighted in yellow, and other topics you wish to follow are highlighted in pink. Highlighting can be controlled on a thread-by-thread basis. It can also be temporarily disabled for all threads using a checkbox on the recent activity page.
First, you'll need to get greasemonkey if you don't already have it. Then right-click the following link and select Install User Script... (If you are upgrading from a previous version, you should be able to install the new version without losing any tracked threads.)
Install the Flickr Group Tracker v1.0
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