I would recomend looking at what you can attain, and buy the items that are least likely to get upgraded. So first off do you pug ICC at all? If you do, I doubt any guild that lets you pug grab an T10 upgrade token. In 10 man ICC for the first wing your looking at a weapon, neck, chest, shield, ring, legs and wrists as drop upgrades. VoA drops gloves and legs. Last item I would spend tokens on are legs. Also you can build legs with the primordial saronite so there is another strike against legs. Most guilded raiders im aware of are getting 2 peice T10 and thats it. Upgradeing thoes and the rest just get drop upgrades. Cataclysm will be out before anyone has a full set of T10 as well as upgrade tokens etc.

My first purchase was the T10 Gloves, This was before VoA came out but oh well. I do raid 25man ICC so I needed at least one T10 item to be eligable for a token drop as a guild rule and the gloves were better than the shoulders. My next upgrade will be the STA trinket. I have the black heart and the gossimar trinkets right now. I do have higher iLv trinkets like the one from onyxia and Ick, but I cant give up 230ish stanima for 100 dodge and parry just for a higher gearscore. My next upgrade will be my boots with the crafted saronite ones. I will have enough primordial saronite to make them by tomorrow from my alts. After that my next badge upgrade will either be the belt or another T10 item if I win a token. Im also on of two MT/OT in our guild now with the other being a druid so tanking plate all goes to me right now.