I have experience the above matter. My home page blog penalize become PR0 but the inner page still in PR1 and PR2. I think that penalize will impact on whole site page but it is not. Do you have any experience like that? Why it is happen?
I don't think so than you are penalized but your inner pages have more value and quality than main page. That's why their is pr in inner pages . Their are many case with other members too on dp .
Your homepage must contain something which is not good and hence gave reason to Google to penalize your homepage. You can review your homepage again and see if something is against Google, remove it immediately.
This is happen on my blog on blogspot and all blog post containing same topic. Therefore, this is confuse me. Anyway, I still receive traffic from google because penalize only for PR, not the URL.
Pagerank does not matter 0o all that matters is the number of links you have, all pagerank is like a display and it means nothing. As long as you didnt lose links its okay
YES I have seen this exact thing from Google and it just shows how screwed up they are I saw a solid, pr4 site that was a blog, and for no good reason, Google made it Pr0 this week, but there is still an inner page that is pr3 so why did google make the homepage pr0???? there was no reason for it either, it is really ridiculous