Watched a recent APS "Conversations with Philatelists" interview with Mark Rosenberg, CEO of Hip eCommerce. A good interview (not too long) about Hipstamp and what they see as their strengths & future plans.
One stat I found interesting - for 2020, estimated eBay
stamp sales of $350M, Hipstamp $25M. Their 5-year plan is apparently to match eBay
's numbers, which is ambitious to say the least.
Apparently there was an earlier interview with the Delcampe CEO too, haven't watched that one as yet. All Stamp Talks are easily accessible on the APS site, lots of good stuff there.
Edit: Corrected name.