Is anybody else having this issue/problem?

[Xtrigit]

I recently upgraded from 3.8.4 to 4.0.5 and google has not cached any of my pages since.

Google does crawl my site but not as frequent as it used to prior to the upgrade.

Whenever I click the [cached] link next to the search result, I get a message similar to this one:

Your search - cache:[randomcode]www.site.com/thread did not match any documents.

I also took a look at the webmaster tools page and it seems like google stopped keeping record of search queries etc the day I upgraded.

Here is a screenshot of the graph:


Is there anything I forgot to do? what should I do?

P.S. Existing threads(indexed pages) that have been recrawled by google bot after upgrade are slowly getting dropped. =/

Thanks