Some people believe that adding followers to their Twitter account is like building a list for email marketing. You have to realize that 90% of your followers are probably robots, and most of the HUMANS will probably miss your Tweet if they have too many followers. Email marketing will always be better and much more personal. Readers will really feel like you are talking to them. In Twitter, you are just sending out a Tweet hoping that some people will read it. In my opinion, Twitter is nothing but just filled with people posting their links. I find the affiliate links to be quite amusing.
I don't know that I would go so far as to say that Twitter is just affiliate links, but you're right that it's nowhere near email marketing. I like this forum by the way.
No, actually both are the different way but focusing on the same target, twitter has it's own beauty, where you have to present yourself in just 140 characters exploring all the beauty of your services and products, it should be sense-full and your followers should be added according to your niche, then I am sure you would get the targeted visitors and would be able to generate the leads. Email marketing is another way to promote your products and services, if you do bulk emailing or don't have genuine email ids, then its 100% chance that your mail would go in the spam coz email service provider has become more sharp and cleaver today. Your server should not be blacklisted, coz the mail drop in the spam folder isn't check by anyone and you miss the chance to get the visitor.
Email marketing and twitter are two different fields but can spread the same message but the way is different