On the other hand if you want to feel good for AMD you could also think that the release of a 2700K might mean Intel felt the 2600K wasn't enough vs BD. After all why would Intel create even stronger competition for their unreleased SB-E?
No. If BD was truly competitive per core, then AMD would have released lower clocked versions of the CPU in Q1/Q2, and as yields improved, simply launched faster versions of BD with revised steppings in Q3. Secondly, if BD was fast per core, AMD wouldn't need 8 core FX-8100 to compete with a 4 core 2500k/2600k. It's obvious that BD can't compete on a per core basis which is why AMD is desperately trying to ramp up clock speeds with 4-5 re-spins now. If this wasn't the case, we would have seen BD at 3.0ghz speeds already. If AMD improved IPC by only 10-20%, a 2.9-3.1ghz FX BD would
easily beat an X6 1100T. But AMD didn't launch such a processor.
Also, Intel has released faster processors before to "compete with itself" as you put it. Core i5 750 and i7 860 were updated to i5 760 / 870 despite no competition from AMD. i5 750 and i7 860 are still faster than anything AMD has. Also, when i7 860 launched, it cost the same as i7 920 but had 2.8ghz clocks vs. 2.66 on the 920.
Don't forget that SB-E is primarily a 6-core platform aimed at enthusiast / workstation users. I am not sure why people keep comparing a 4-core SB-E to 2600k/2700k since the slowest 4-core SB-E doesn't make any sense to begin with after taking into consideration much more expensive mobo + 4-channel ram requirements. Intel had i7 920/930 CPUs on more expensive LGA1366 while you could have purchased i7 860/870/875k cpus on cheaper 1156. So having a faster clocked 2700k to be at least as good as their slowest 4 core SB-E is nothing unusual.
Finally, if Intel was worried about BD, they would have pushed IB launch forward, not back to Spring 2012 at the earliest.