Does MAC OS X Lion support any BluRay Burners? I would like to burn my edited videos to HD BluRay discs.
Yes. Though you need separate software to author Blu-ray video. Most Mac users prefer Roxio's Toast Titanium. You also need to purchase the separate Blu-ray plugin so it actually will burn Blu-ray video disks. Once installed, you can author your disks right in Toast (somewhat limited), or do the authoring in your video editing software and burn the finalized BDMV folder in Toast. Either requires the plugin.
What bluray hardware/burner should I buy?
Up to you, but Adobe recommends Digistor-Panasonic drives (Panasonic hardware is what Digistore uses in their enclosures). I've been using an LG internal drive in my Mac Pro for at least a few years now. No problems with it. Here's a page of external burners.
(Is a "Plugin" the hardware?)
No. The plugin is a secondary piece of software you need to purchase from Roxio to burn Blu-ray video disks. Without it, you can only burn Blu-ray data disks.
avoid the BDR206
Hmm, I wonder why that model is so bad? Doing a Google search for "BDR206" flat out states do not use on a Mac. Actually, the topic text you see in Google states that. Reading the actual thread, a person there sells them by the thousands to Mac users, who have no issue with that model at all.