Hulu has once again blocked Hotspot Shield users from using its service. After about 3 days of working again, it appears the new IPs have been collected and placed in the filter. It's pretty clear that there's pressure to keep the geo-filter working. I'm guessing Hotspot shield will have new IPs allocated fairly soon and once again work, but it's just a matter of time before Hulu blocks them yet again.

Update: Seems to be working this morning again (as per Adrian's comment). Not sure if it's a different IP from last night, but both locations appear to be New York. Could have been that my HotSpot Shield connection died and I didn't notice.