Tick Tock - When Am I Eligible for a Phone Upgrade???

I check about once a month at Sprint’s web site, but I think now that I am going to have to change to Verizon.  And what a change that will be (me, mom, daughter, air card - hubby is already there). 

If my darling Sprint would carry this absolutely incredible pink Blackberry Pearl 8130, it would solve all of my problems (pink, camera, I’m sure I have others).  Never mind that I’m not eligible to upgrade from my big ol ugly BLACK berry yet.  But when I am, Sprint had best be carrying pink, that’s all I will say.