Although electronic communication differs strongly from print collateral as a medium, make sure anything you send out is consistent with the rest of your marketing efforts.
Don't convey one company image in your ads and a different one in your e-mail communications. Keep them similar through language, tone, or judicious use of images. If you are offering something only to your e-mail customers, highlight the fact in the e-mail itself.
Also, make sure you send your e-mail from an address with your company name in it. Sending e-mail from a generic address or an alternate e-mail address can cause confusion and make your business look unprofessional.
Conclusion - Make your e-mail communication
consistent with your corporate image. And use a from address with your company name in it.