For comparison's sake, here's Eric Cantor's comment on the ozone standard:

Ozone Rule (Winter): This effective ban or restriction on construction and industrial growth for much of America is possibly the most harmful of all the currently anticipated Obama Administration regulations. Consequences would reach far across the U.S. economy, resulting in an estimated cost of $1 trillion or more over a decade and millions of jobs. Unlike her predecessors, EPA Administrator Lisa Jackson is pushing for a premature readjustment of the current ozone standards, dramatically increasing the number of “nonattainment” areas. The new readjustment rule is expected early this fall and I expect the Energy and Commerce Committee to act swiftly to prevent its implementation, in order to protect American jobs.

Jackson has recently stated that the Bush-era ozone standards are legally and scientifically indefensible (pdf). However, the ozone standards were due July 26 and have been delayed for some time. Now we know why - a White House decision.

Update - reactions: McCain, McConnell, and Inhofe approve. Markey doesn't. Boxer issued a statement in 2008 attacking the Bush administration's delay, and many are wondering what if anything she'll say in response to this decision. The White House blog emphasizes actions taken by the White House, other than ozone, to enforce the Clean Air Act.

An anonymous friend working in the regulatory/clean energy business tells me that the delay - it's a delay, not a withdrawal, s/he says - is needed to plan around a regulatory stranglehold. S/he tells me that the regulations will gradually end coal plants so that natural gas plants take over, but the natural gas plants will also be regulated out of existence by 2030, and there won't be enough renewables to power the United States.

Update 2: Brad Plumer has the best explanation to date on whether the White House double-crossed enviros on the smog rule. A senior NRDC attorney has confirmed to me that a NRDC lawsuit will be revived, and TomP has posted regarding a similar move by the American Lung Association.