There hasn't really been a good comparison test between the current-generation Intel processor and the next-generation Haswell, but a certain tech publication claims to have successfully run a benchmark.
The name of the tech site that has published the findings we are about to discuss is OCLab.ru, and the chips compared in the benchmark run are an Ivy Bridge and an engineering sample of the LGA1150 Haswell.
The reason Haswell couldn't be benchmarked before is because engineering samples of them are scarce, and there aren't many LGA 1150 8-series motherboards to go around.
OCLab.ru claim they have both, and we'll assume the information is true until someone says otherwise.
The Russian website didn't push the chips all the way, and didn't really say what the chip models were, exactly.
Instead, it limited them both at 2.8 GHz and did a clock-for-clock comparison in SuperPi 1M, PiFast, and wPrime 32M.
As the screenshots on the left show, the Haswell proved just a bit faster than Ivy Bridge, albeit slower in one test.
More tests, where single-threaded performance was examined, showed a wPrime 1024M performance nearly identical between the two, and SuperPi 32M results where the Haswell was 3% better.
Turbo Boost, C1E, and EIST were disabled throughout all the benchmark analyses.
Overall, the Haswell architecture doesn't appear to have very significant improvements in terms of raw power, meaning that efficiency and higher clock limits might be Intel's focus here.
Then again, the next generation of Core-series CPUs won't be out until June (2013). Six months are more than enough time for this initial impression to be challenged.
For those who need a reminder, the 4th generation Intel Haswell CPUs are scheduled for a Computex 2013 reveal. Computex is a show taking place in Taipei, Taiwan in the sixth month of every year.