I'm interested in statistics (especially from websites with non-technical and international audiences) about what percent of visitors are using browsers/devices that don't support SNI.
I don't know how representative this is, but it looks like StatCounter Global Stats [1] says that slightly over 10% of recorded visitors are still using Windows XP, and many of these users won't have SNI support.
Small websites without strict security requirements often use shared hosting, where SNI is the only practical way to implement HTTPS. Alienating something like 10% of visitors with a security warning is probably not desirable. I imagine this could be a not insignificant roadblock to widespread SSL adoption on small websites, but would like to see more detailed stats.
http://www.utilitydive.com/ is a US-based news site for the electric utility industry. About 4.5% of visitors are on Win XP and most of those people are using XP. It's trending down pretty sharply; it was nearly twice that at the start of the year.
I don't know how representative this is, but it looks like StatCounter Global Stats [1] says that slightly over 10% of recorded visitors are still using Windows XP, and many of these users won't have SNI support.
Small websites without strict security requirements often use shared hosting, where SNI is the only practical way to implement HTTPS. Alienating something like 10% of visitors with a security warning is probably not desirable. I imagine this could be a not insignificant roadblock to widespread SSL adoption on small websites, but would like to see more detailed stats.
[1] http://gs.statcounter.com/#os-ww-monthly-201307-201407