Replacements are thicker, less prone to break HDTVs.
The day after Nintendo President Satoru Iwata announced his company would be investigating the Wiimote strap issue, likely due to rabid Internet discussion and mainstream media attention, GoNintendo discovers they've already started issuing a solution in the form of thicker, better replacement straps.
Chances are Nintendo will start incorporating the new straps into future shipments of Wiimotes, but what about the thousands whose straps have already broke (i.e. me, Nintendo!)?
Source