Readers of this blog know that I've been saying, for a long time, that META tags are not very useful and, for the most part, not worth your time. Do not waste your time and money developing META tag generators. META tags will not help you get your site ranked higher.
The only value of META tags is that accurate META tag information may help in clickthrough. Google and other SEs will sometimes display the META description in their results page.
See Meta Tags and Title Tags