t-zones no more?

My trusty Nokia 6600 has been on the fritz so I've been looking for a suitable alternative. Unfortunately any other smart phone isn't really compatible with T-Mo's cheap wap plan (4.99 when I started up).

And now I found out that T-mo is phasing out t-zones for a more lucrative plan. Depending on the chosen plans, web access may be capped to a certain MB/mo and messaging is bundled.

Now if my phone does die, it's a very high likelihood any replacement phone from T-mo will only be compatible with the new, more expensive plans...

I wonder if unlocked phones will have the same issue...