Damn right. On most French TGV, you can't plug your laptop, so that either you're on your own power, or you somehow know which trains do offer the possibility, or maybe you travel first class.
Just plain old 220v. power on a recent electrical train : it can't be such an engineering challenge ?
The ICE from Munich to Frankfurt even has WLAN (I haven't actually had a chance to try it yet), and this should be extended to Hamburg by the end of the year.