I've followed the rumors of an upgrade for the Curve for more than a year now, back when the version was rumored to be 4.3. Since then, we've learned of and witnessed the release of the Bold, the Storm, and soon will see the Javelin. Every time a new model was announced, speculation that an updated OS for the Curve would follow, and every time it hasn't happened.
Seriously, OS 4.2.X is well over a year and a half old. Other carriers have released updates, so it's not an issue of hardware. I believe ATT has decided it's not in their interest to update the Curve. Why not? The cost of supporting an old platform and possibly causing users to hold onto their older Curve instead of buying a new phone.
No question, v4.2xx has reached the end of it's development, but v4.5xx midlife refresh keeps it current. Diehard users will continue updating with each update.
It will continue to be like Christmas, every month.
