RLV News points us to another update from Masten with a lot of pictures of tether testing setup. According to a comment in the post there very well may be more to see at Masten's blog this weekend, so check back there.
Update on June 23: I just checked back and there's already a new Masten post about the testing called T minus XX.XX and counting... The post says they'll return tomorrow (I'm not sure which day "tomorrow" refers to though as the activity sounds like it was on Friday night and the post date is Saturday morning).
Selenian Boondocks has more about the Masten testing in a post called "Mach 10 Butterflies".
Update on June 24: Masten has more videos and comments on the videos from this weekend's testing. There is also an earlier video showing why they were concerned during one of the tests.