Co-founder of Webpop here. Honored to see our landing as one of your examples :)
We actually had exactly this discussion internally when we created our landing. We even had at least one prototype of the more mysterious kind with little more than a signup form.
I think both can work well, but for our beta we felt it was quite important that our users had an idea about what they signed up for. We're not doing a consumer product, and it wouldn't help us much getting lots of emails from people who would be completely lost when given access to a tool for professional web designers.
I suspect that being more mysterious would work well for sites with more of a social networking or entertainment focus.
Co-founder of Webpop here. Honored to see our landing as one of your examples :)
We actually had exactly this discussion internally when we created our landing. We even had at least one prototype of the more mysterious kind with little more than a signup form.
I think both can work well, but for our beta we felt it was quite important that our users had an idea about what they signed up for. We're not doing a consumer product, and it wouldn't help us much getting lots of emails from people who would be completely lost when given access to a tool for professional web designers.
I suspect that being more mysterious would work well for sites with more of a social networking or entertainment focus.