It's better than it used to be. We have 4 major browser vendors now, Apple (Safari and iOS), Microsoft, Google (Chrome and Android), and Mozilla, all of which have plenty of market share and none of which have most of it.

There was a long period of many years when IE was king and anything else was irrelevant. There was also, even earlier than that, a period where Mosaic/Netscape/Mozilla and its kin were dominant.

This is the best it's been in a long time in terms of no single browser maker controlling the market.

Indeed, there was a set of roots IE 5.01/NT4 SP6/Win2000 and later trusted, and at that time only XP did automatic root cert update making them very valuable. Just before then, I think IE/SChannel only trusted VeriSign/Thawte/CyberTrust, and VeriSign bought Thawte just after IE 5.01 and NT4 SP6 was released.

It will be interesting to see what happens when a Chrome user can't access his bank web site because of this, and the bank tells her to switch to Firefox/IE/Safari.