"Lively" is such a new offering [webmasterworld.com] that no one would have enough time to talk about real-world results.
When it comes to PR, that only comes from your backlink profile. If adding Lively functionality ehlps earn your site more more natural backlinks, that can help PR. But links will mostly be based on what you do with Lively, and not the mere fact that you've got the technology.
I remember talking with various animators in the 90s who envisioned VR stores on the web as the ultimate portal.
I'm sure it could be done well in some instances, but IME a virtual store front would make for a less efficient and streamlined user experience than plain old web pages. It's hard enough making a 2D site that is easy to use for 95% of your users.