Even though this was expected, it's still a bit of a bummer. It seems T-Mobile has decided to boost their wireless data prices for customers that have plans with the carrier on smartphones. Like during the whole credit crisis, people need their monthly bills increased.
The wireless data plans used to cost $19.99 for unlimited data, so long as it was in conjunction with a voice plan. But now you can expect to pay $24.99 a month. However, your usage is no longer allowed to be unlimited. In fact, it has a cap of 400 SMS or MMS messages. If you want an unlimited plan, you're going to have to shell out $34.99 a month.
Now remember, folks, this is on top of a voice plan. If you got a T-Mobile G1, you were automatically signed up for the $24.99 a month plan.