Hi Shirlea,
if you're interested in an alternative platform where you can work collaboratively with your DNA matches (in a similar way how we work together at WikiTree), please head over to Your DNA family which is currently in Release Candidate (RC) phase just prior to General Availability (GA).
The reason why I bring this up in your G2G post is that we're planning the same feature that GEDmatch offers (comparison of raw DNA data for the purpose of automatic triangulation, which we currently offer already for 23andMe exclusively.
So there will be future 2nd alternative to GEDmatch but with many more features on top.
A future integration with the WikiTree family trees is planned, depending on the API capability here at WT. Especially for an easy import as we also identify MRCA (most recent common ancestor) and common ancestor (CA) automatically.
DNA matches can join for free as "guests" similar to Ancestry's guest account feature. Otherwise the app is build on a subscription for the automatic triangulation, chromosome map, network graph and the discussion forum you get for each TG (triangulated group).
For everyone interested we do have screenshots and video available on our Facebook group Your DNA family FB.
Disclaimer: I'm the "brain" behind this DNA genealogy app