There are some devices, cheapest I found was around $200, which allow you to capture from HDMI via USB 3.0... which may allow you to view the feed as it's coming in -- I don't know...
The cheap one I found was "Blackmagic Design Intensity Shuttle for USB 3.0 Computers"
http/www.amazon.com/Blackmagic-Design-Intensity-Computers-Professional/dp/B003WSQTWU/ref=sr_1_4?ie=UTF8&qid=1326755265&sr=8-4
Unfortunately, this device seems to need a desktop chipset (Intel X58), so may not even work for a laptop...
In the comments for that one on Amazon, a user mentions that PS3s output with HDCP on the HDMI signal, so this type of unit won't do anything with it directly, but then he also mentions a couple ways around this.
There are others built for the video editing industry, including a model from Matrox, that folks use to record their console gaming sessions, but this class of devices seem very expensive, you'd be better off with buying a monitor, or coming up with some sort of "plan B".
Good luck!