I just purchased the Omni Groups bundle, OmniOmniDiskSweeper, OmniOutliner, OmniGraffle, and OmniWeb 4.

I like their products. I hope they add the ability to edit opml files with OmniOutliner and the best way I know to make that happen is from the inside, by becoming a customer.

I'm going to create site maps using OmniGraffle. This is a great app.