Probably 32-35°C. Don't worry to much about your idle temperatures, instead, focus on what they get at full load. That will give you a better indicator if your CPU cooler is seated (or working) correctly.
Also depend if you are stock and/or using "C states".. With C states enabled and a good air cooler like hyper 212 at 27C room temp yo should be in the 29-31C. I had one hyper 212 for a long time in my i7 sandy and with C states the idle temps was always 1-2C highier than room temp.
I'm under water so YMMV, but I'm seeing 25-30 with a 240 and a 200 rad. Load temps are what you should be looking at though since the processor downclocks at idle to save power and whatnot.
Load, with a 212 or other good air cooler you shouldn't see more than like 60 at stock. My friend was getting 60 at 4GHz on his 3770k.
I hit 67C in Parallels+OS X near-idle, and 77C on one of the cores on the iMac at 28C (measured on the other side of the room) ambient, while in barely-stressing use in both Parallels/Windows 7 and OS X (and not working both at the same time). I'm sure Anand and the like fall over themselves to slobber praises over the machine but it's barely usable in summer ambients, which isn't new for a Mac, especially the iMac - but I really haven't seen figures like these for a long time.
Winding up the squirrel wheel to the point that it was dumping worthwhile amounts of heat (but still running in the mid 50's) made it the noisiest thing by far - and there are dual E5-2687W's with dual GPU's also around - in the room.
I have other machines with 3770's but since I just pinged my back again I was not about to lug the XPS 27 Touch over to the study (but even by a process of extrapolation it runs way cooler).
That looks a bit too high for comfort, even on air. Especially for that amount of load that you're putting on it. I usually try to stay under 75 on a full load.
Yeah - as I said before, needing to run the squirrel wheel at jet engine levels to stay in the 50's at idle isn't exactly my idea of stable. Mind you, this is pretty much par for the course for any Apple piece of crap - but I don't have an option of buying Pro's, at least not new, here right now (they at least stay at badly-built PC levels, if not equivalent-workstation levels) to top up my desktop Mac roster.
However, I've heaved back Pro's (that I really need to be elsewhere, but still) to my desktops for the time being as the daily Macs and am waiting for the 680s to arrive for all. The iCruds are going to be kicked to the curb until I figure out what to do with them.