Need some guidance here,

I have decided to buy a 1.6 GHz G5, 1GB Ram, Radeon 9600 Pro Video Card, 17" studio display Mac!

I just wanted to know whether I should buy it in March or should I wait? I heard that Apple may release a 2.5 GHz. If they do release the 2.5 will they still have the 1.6? if they do will the price be lower? or will they make the 1.8 cheaper?

Need some guidance here, so any advice is greatly appreciated!