You script doesn't seem to be working. I just checked my pr4 blog and it showed pr0 here. Lemme PM you that particular blog.
Well, the idea is ok... but: a) the script is (tremendously) slow, b) some colors are really screaming "Go away I don't want to have users using this website", c) the PR are totally wrong. Re-design it! It's easy, just with a bit of CSS3, make a selection of nice colors to improve the user experience and rewrite the PR script. I suppose you use just one Google server to check it, right? Well.. if you abuse it... and I mean with a lot of requests the server will IP ban you! That's why I believe the script is not working and do something smart... create a cache system for the results!
The pr is coming from only one source, from here, this is the link used: http://www.google.com/search?client=navclient-auto&ch=6$checksum&features=Rank&q=$url Code (markup): If the pr is not showing correctly is their fault, not mine
As I thought you use just one server, the main of google.com that after some uses of the script for sure banned your IP address so is returning "0" for every domain you query. As I already said in another thread, you should rotate the google servers used to query the pagerank and also use a valid "user agent", if you are using curl to query the address, curl as User Agent will use something like "libcur v.xxx" and google will ban immediately all the IP using this kind of user agents. I don't like making advertisement, but if you go in http://chkme.com/page-pagerank-check you will see that the PageRank check work for this kind of reasons: a) I use 13*** different Google servers; b) I use a cache of 24h for every queried domain - Pagerank don't change in few seconds; c) I use a valid User Agent also using cUrl. By using this kind of "tricks" I avoid google thinking to ban my IP. *** I am sure that one of 13 google server have banned my IP so I know it will return 0 for everyone... in fact I am investigating which is and I believe is the "toolbarqueries.google.de" server.