I've only had the device for a couple of days now but haven't noticed any adverse effects. What prompted me to try it in the first place was [this ZDNet article][1], in which the author adds, "...my Skype video call to Jason Perlow was an hour long with video, and battery was down to 91 percent when ended."
[1]: http://www.zdnet.com/blog/mobile-news/overclocking-the-hp-to...