That looks about normal. My i7-920, when i had the stock cooler, loved to idle in the low to mid 40's (winter/spring/fall) and low 50s (summer) and gets up to mid 60s/70s under load.
You can run it above the recommended temperature no problem. It may reduce the life of the processor but it'll be far outdated by the time it actually dies (think several decades in the future -- minus a couple months).
Advice -- Clean the heatsink out every now and then or invest in a good one like a Hyper212+ / evo and drop 10c or so in idle / 10-20c on load.