That's true in a few cases, but on many big issues, he has continued or even expanded Bush's policies. They've already been listed in this thread, but I'll repeat them for you.
things that have been kept the same:
- warrantless wiretaps
- Gitmo
- Patriot Act
All policies supported by the viable GOP candidates. If you wish to look for opposition, you will have to look to the Democrats in Congress.
- opposition to gay marriage,
Personal opinion, also shared by the GOP candidates. There is no Obama policy on this issue.
Bush policies that Obama expanded:
- Bush increased spending on health (Medicare part D), Obama added Obamacare
Which cuts medicare spending over the next ten years.
- Bush increased spending, Obama increased it further
Bush tax cuts benefitted the wealthy most.
Obama's tax cuts benefitted the working class the most and stimulate the economy more.
- Bush supported policies that led to the mortgage meltdown, Obama kept those policies and added an $8K tax credit
Obama supported financial regulatory reform which the GOP oppose.
- Bush bailed out the banks, Obama supported that and bailed out GM and Chrysler
Without the bailout, the banks too big to fail created by deregulation, would have caused the economy to collapse. Without the loan to GM and Chrysler, our unemployment and economy would have been worse.
There are examples of Obama reversing Bush's policies. I applaud him for ending waterboarding, but for the most part, Obama kept Bush's most hated policies and expanded them in some cases. His two biggest policy initiatives (ARRA & Obamacare), are anything but policy reversals. We're still going the same direction, only much faster. Bush was Obama Light.
You ignore the financial regulatory reform, and the increased revenues proposed under Obama. Romney is just promising more of the Bush policies that drove us into the ditch to begin with.
Edit: I also applaud Obama for repealing DADT. I'm glad that he supports nuclear energy, supports ending corporate tax loopholes and reducing the nominal rate, and supports cutting military spending, but those things haven't materialized yet.
The first nuclear plants in over 3 decades have begun construction, the cut to military spending are already under way, the Pentagon as already announced they will comply. The elimination for the tax cuts for the wealthy will require some seat changes in the House in November.