As much as I don't want to leave the heavy customization of my SL, I will mostly likely upgrade.
You know that the only program that currently works with Version is Textedit, right?
If it can't do fresh installs, Apple has just lost me as a customer for Lion
It is also going to be supported by at least Preview and Automator right away. [Source]
You know that the only program that currently works with Version is Textedit, right? iWork will also get updated to work with versions, but for me and many others I am sure, Versions means nothing till MS Office supports it.
They still have a month to before Lion is available. Plenty of time.