At first I was not going to confirm or deny anything. But a lot of people were freaking out to me in emails and such, and I do not want anyone upset with Britney... so here you are.
Britney is NOT cancelling any shows as previously stated by several popular blogs. All 4 shows as scheduled will continue, unless she decides last minute to pull out (which is always a possibility). The shows will go on as planned in San Diego, Anaheim, Los Angeles and Las Vegas.
Hope that helps.