Been mulling over a name for a new website and was checking out the availability of some names that we came up with.

All the versions with a "to" in the name are either in use or parked but the versions with the "2" instead of the "to" are almost all available...

What do people generally think of replacing words with numbers in URLs, does it matter to the enduser? do they care as long as the site gives them what they want?

Would there be any positive or negative SEO effects?