Created attachment 528914 [details] video of hang With up-to-date F16 beta: 1. Run wireshark. 2. Select Capture | Options... 3. Select your external network interface. 4. Click in the "Capture Filter:" text box and try to type "host <whatever>", where <whatever> is the host you want to filter on. 5. The text box turns red after you type "host " and then wireshark hangs and you have to kill it. Video of this sequence is attached.
It works for me with wireshark-1.6.2-4.fc16.x86_64. Wireshark interactively as you type checks, if 'host whatever' is valid filter, i.e. if 'whatever' can be resolved to IP address. This is usually quick enough so you don't notice it, but if your DNS is in bad shape or down at the moment, it might take some time for wireshark to give up trying. So, was there something wrong with your DNS? And you might also hit bug #747377, please update your Wireshark to latest version and try again.
This was not a DNS issue, it was a hard hang. I never even got to the point of being able to type the host name after I typed "host ". As soon as I typed "host " in the field field, wireshark hung and nothing I did unhung it. Having said that, you're correct that it appears to be working now with current stuff from F16, so it appears that whatever was broken is now fixed.