The last point in the FAQ seems to say no, they will not be put into the ICO:

26. Will block.one be contributing to the EOS Token distribution?

No, during the entire EOS Token distribution period, block.one will not do any of the following:

• block.one will not purchase EOS Tokens by any means;
• block.one will not pay any dividends to its shareholders; and
• block.one will not perform any share buybacks.

block.one intends to engage an independent third party auditor who will release an independent audit report providing further assurances that block.one has not purchased EOS Tokens during the EOS Token distribution period or traded EOS Tokens (including using proceeds from the EOS Token distribution for these purposes). This report will be made available to the public on the eos.io website.

That said, what the individual employees do with their own money or the money they get paid? That's a different story. I assume the 10% they are keeping for themselves is the incentive to keep the team motivated.

As to it being on ETH, that's also covered in the FAQ a bit. I think if there was a better, decentralized, transparent, provably secure way to do it, they would. ETH seems to be the best approach available right now and Dan generally seems to go with the best approach available on stuff like this.