Going to have to find the link later, but I'm sure the dual core chips are being delayed to clear Sandybridge inventory of dual core chips. If that is the case, then Apple could easily get hold of them as it's not retail. Especially when you consider they got SB 1 week early last year which suggests a reasonably cordial relationship with Intel.
The media event thing, I can't disagree with. I would be shocked if Apple did a quiet redesign or retina display upgrade. I could however, foresee a simple spec upgrade to Ivybridge tomorrow. I'm not going to get into a debate how likely a spec upgrade is vs complete redesign. It has been done to death.
Edit:
http://news.softpedia.com/news/Intel-Delays-Only-Some-Dual-Core-Ivy-Bridge-CPUs-253767.shtml
"More precisely, due to the large supply of Sandy Bridge central processors, the Santa Clara, California-based company is putting off the release of dual-core mobile units."
"The supply of Sandy Bridge CPUs is said to be so high that not only are vendors overstocked, but also even Intel's own warehouses still have shipments that, had sales been better, would have been sent out quite a while ago."