WORST: Houston, What's The Problem? Whitney's Concert Disasters

Whitney, what's wrong?

Pop legend Whitney Houston may not be on drugs anymore, but the weight they carried clearly hasn't lifted.

The singer, currently embarking on a world tour supporting her successful comeback album I Look To You, is facing intense criticism from fans and the press after a string of lackluster, if not outright terrible, performances.

Her latest concert, at London's O2 Arena, was apparently so terrible that some fans walked out of the show after only twenty minutes, even though some paid up to $156 for tickets. Whitney, who was diagnosed with a respiratory infection, struggled to hit the famous high notes in songs like "I Will Always Love You". She wasn't able to finish her classic hit "Greatest Love of All", stopping after a few verses, according to reports. She blamed her vocal issues on the air conditioning, and even referred to her powerful pipes as being "temperamental".

Another major criticism was her appearance. The diva appeared haggard, bloated, and out of shape at the O2 Arena. It comes as a major surprise, since Whitney has been looking fantastic for most of the tour so far.

So, what's wrong with Whitney?

While she reportedly was hospitalized for a respiratory infection in Paris last month, criticisms of her vocal performance appeared long before then. The Australian leg of her tour was viciously attacked for what concert-goers considered terrible vocals. Her croaky voice has been blamed by her concert promoters on her smoking habits, while it also possible that the drug abuse in the last few years has left irreversible damage on her voice. Finally, she just may not have been physically ready to do such an extensive tour spanning Asia and Europe so far (no North American plans have been made).

I am a huge fan, and she can deny it as much as she wants, but there is clearly something wrong in the world of Whitney. Let's just hope she can fix it before her comeback is officially tarnished.