servie? help please? Im planning on buying a brand new unlocked iphone 3g 8gb off of ebay and im already with tmobile (little over a year left on contract). ive done as much research as i can on my own and everything says that i should be able to use my sim card in the iphone. I currently have a sidekick and a FULL data plan-internet, unlimited text/pic msgs, and unlimited minutes. When i put my sim card in the iphone will all of those features on my data plan transfer over to the iphone?? Also-does anyone have personal experience with using the new iphone 3g with Tmobile service?? How has it been for you? good? bad? Also big thing-do i need to tell tmobile that i am now using the iphone instead of the sidekick or will they already know? Also what is the cost to use the iphone with tmobile? is it just the same price as your current plan-i am now paying $65/month. Thank you so much to anyone that has any information 