Thanks to all the advice members on this forum posted, I attained Platinum status in December 2006 and at the rate I am going should retain it next year too.
My latest experiences may help a few people who are having difficulties obtaining points for which they are entitled.
My family and I stayed at the HI Surfers Paradise for 6 nights over Christmas using a PP $110 voucher (3 nights), a PP BOGOF voucher and one night on an advance purchase rate. On check-in my Platinum status was not recognised so I enquired whether an upgrade was available. I was told I could have an UNrefurbished room a few floors higher or stay where I was (Floor 14) - I opted for the latter. A week after I returned home I still had not received any PC points so I sent off an email to the hotel. I was advised that as I was on a deeply discounted rate I was ineligible! So I immediately emailed the General Manager who apologised and arranged to have the points credit to my account.
In February we stayed at the CP Darling Harbour for 2 nights. My platinum status was immediately recognised and I was upgraded to a Darling Harbour view room and given a boxed bottle of red wine. Again a week passed and again no points. The same response was given to my email as the HI. Yes, I emailed the General Manager and received an apology and was told I would also be getting "a surprise gift" (which turned out to be more points).
I also brought to both managers' attention that I may have been on a discounted rate, but I also spent $$$$ in the restaurant and on parking (at CP).
This last weekend I spent 2 nights at HI Potts Point. I was immediately recognised by the delightful Maltese receptionsist as a Platinum PC member and received an upgrade to a Harbour View room, a BOGOF drink voucher, and while we were out, a hand written thankyou/enjoy your stay card was placed on our bed. I will certainly be staying there again! Hope I dont have to go through all the hoo-ha to get my points this time.
My Platinum status has certainly encouraged me to be a loyal member and not to stray to other hotel chains.