Absolutely good points.    Privacy and security can be issues.  I know that there are good ways to secure emails including using anonymous remailers to hide IP Addresses, using PGP encryption for attachments, not writing into the body of the email and sending all correspondence via the attachments, third party providers who offer verification of delivery through small scripts, one-time use and short duration email account services, and more.

  After considering and weighing the issues for our firm, we've opted for the convenience of customer access to us over the more dissuasive tools that would, we feel, make us less competitive. 

  Everyone will assess this differently, I'm sure.

  Our firm does not require privacy for our owners.  Our clients are requesting data from public records resources.  We feel that there is little to worry about, as even private emial systems are subject to hacking and might even make one a target to the astute hacker.  Living in Silicon Valley and knowing some such people does put us in a vantage point of understanding their mindsets.