For everyone looking for answers about avian influenza, the best information will be on the BOAH (Indiana Board of Animal Health) website, as well as USDA, CDC, and APHIS websites (federal agencies which all include monitoring or oversight over avian influenza).
I was asked what happens to eggs that may be AI infected. Honestly, I have not found a QUICK answer to that question. I don't know if they survive to hatch or not. For those of us who use incubators and brood artificially, it's less of a concern because any illness that might potentially occur will happen before the chicks are old enough to put outside. For those who use broodies (the "old fashioned" way man has used since we domesticated poultry), it's less clear. An infected chick, if it survives to hatch, could certainly infect the broody and other birds it has contact with. What I do not know is whether these infected eggs survive to hatch. It may depend on whether they carry the low pathogenic (less bad) AI, or the high pathogenic (very bad) AI. In all cases, AI causes hens to decrease egg production and produce thinner-shelled and misshapen eggs.
Here is a more comprehensive website that I came across today:
http://www.cdc.gov/flu/avianflu/ It deals with the illness in birds and people, and what is being do to monitor it (surveillance). A month ago, most HPAI cases were found in backyard flocks. That has not been the case since then. It has hit some very large hatcheries in several states.
I think we are OK to continue to buy hatching eggs and set only the ones that look "normal." I think most of us do that anyway because we're more likely to get a generally healthy chick out of normal looking eggs with normally thick shells. However, if you wish to err on the side of caution, don't use broodies on hatching eggs obtained from untrusted sources. You can certainly use broodies on your own stock. If you are buying from Indiana breeders, you might ask them if they have at least had their flock screened (the free screening of a dozen eggs that I posted about a day or two ago). Testing clear is not proof that 100% of your birds are clean, but that plus knowing there have been no unusual deaths or illnesses among that flock should be reassuring. I would be disinclined to buy hatching eggs from locations near the areas where outbreaks have been known to occur, though my understanding is that besides culling infected flocks, the USDA does surveillance on all nearby flocks for a while to make sure they are NOT infected as well.