Is it possible that even though a pagerank of a website is defined early , it is shown to the user at a later stage ? I came to conclusion after checking Sitemaps which showed page with highest pagerank at website other than frontpage this time .
you came at right conclusion Pagerank is updated in datacenters after a while and then take time to propagate. But google always live pagerank of webpages and in 'fractions' like 4.35342 .. that may get 4 in PR update .. but actually its more than PR4 but less than PR5.
There's a tool at Iwebtool which predict your page rank based on backlinks etc. You can check it out here: http://www.iwebtool.com/pagerank_prediction However, its not always accurate.
No,something changed at sitemaps,the page i created last week is showed as highest page rank for Nov. something weird is happening there.
Yeah sometimes the sitemaps show strange results, for one of my clients sites it is showing the contact page having the highest PR, this can't be right.
Usually sitemaps ( Webmaster Tools) shows quite old data. Serps positions reported are usually very old, the same is for Your page with the highest PageRank