[mapt]

I expect blocking GMail, Hotmail, & Yahoo Mail also cut your conversion rate close to a factor of zero of what it would otherwise be.

[jks]

Here's how that might happen: http://mailinator.blogspot.com/2011/05/how-to-get-gmailcom-b...

[zrail]

Nope. The blocking is only active on certain products over $500 that don't make sense for non-companies to buy.