[CJefferson]

While this is bad, most gems are executable code, which will get executed (seeing as you installed the gem).

So while this is bad, I don't think it's that bad -- a malicious gem could always mess you up. Still update!

[irishsultan]

The only difference is that you are perhaps more likely to install a gem system wide (which would require root rights normally) than run code from a locally installed gem with root rights.