This is odd.  I've been using a 64-bit version for a few months now and entity snaps have been working just fine.  An hour ago, they simply stopped working.  I have all the snap types enabled.  I uninstalled the software and just installed V1R3 x64.  Same thing.  I can do an entity snap using the toolbar or typing the snap type from the command line.  But, this morning the cursor would snap to the various entitys and show the snap type with a little yellow shape.  How could I have turned off this mode??  Hoping it's some bonehead move I did.  But, I've been drawing all day just fine.