USEABILITY: Single or Multiple Forms?

Hi everyone,

I am seeking opinion's on whether or not, it is generally better to have 1 page with a long form or to split this form up into several logical pages. I am in the process of designing a Trademark application Filing process and there is a medium amount of data to be collected.

I can obviously arrange this all on one page in one form but I do not want to overwelm users and scare them away from filing an application with the site (the main goal of course).

On the other hand if I split the form up over multiple pages then users on slower connections have the overhead of opening up 2/3 more pages?

Some Examples:

1Page: URL

Multi-Pages: URL
Comments / prior research all welcome.

Thanks in advance.