It’s taken a while, but the spiders that created the giant web in Texas are now believed to be:
Guatemalan Long-jawed Spider
Tetragnatha guatemalensis O. P.-Cambridge
Family Tetragnathidae – Long-jawed Orb Weavers
This page has a timeline of the web, photos, and the media coverage. It also includes this:
“Initial speculation was that the massive web belonged to a social spider, probably Anelosimus studiosus, family Theridiidae. The email with with photos of the Lake Tawakoni web also included a photo of two Long-jawed Orb Weaver spiders, family Tetragnathidae, but these were considered to be incidental or minor contributors to the massive web as tetragnathids normally make orb webs which were not apparent in the photos of the giant web. ”
and “There were many other spiders in the webs. In order of how common they appeared to be, most common first, I saw Tetragnathids, Salticids, Theridiids (Argyrodes sp.), Araneids, Agelenids, and Lycosids. We even had one Mimetid (pirate/cannibal spider).”
You can see how there was some confusion! After some back and forth, and more specimen collections, the consensus now is that it’s a mass group of tetragnathids.
Many, many thanks to Mike Quinn, who’s done an awesome job both documenting and puzzling out the web.