1.1G is 1.1 billion. Or written another way:

1,100,000,000

Like a "gigashare" or something? Would a trillion difficulty share be T for tera, and a quadrillion difficulty share be P for peta?

It's exactly that but it's called Gigahash.

I thought a gigahash is a certain number of hash calculations, e.g. 1 gigahash/s is 1,000,000,000 hashes calculated per second. Therefore, I think I'm just talking about one hash calculation that satisfied both the difficulties for an acceptable

*share* value (in this particular case, d=128) and for solving a block (d=68.2M).

That's why I called it a giga

*share*, and I put it in quotes because I wasn't sure what else to call it.