Anybody with shares in their TFSA should be concerned about an exclusive NASDAQ listing, simply because you'll eventually be hit with the 15% withholding tax imposed by the American government when you sell. Not really an issue for regular trading accounts, as you get a corresponding tax credit, but TFSA's aren't subject to that credit, so a chunk of your profits will simply disappear.

If POET wants to offer a kindness to the long-suffering Canadian shareholders (who have been and continue to be the majority of backers), the expense of uplisting to the TSX shouldn't be an issue. Actually, I've been quite surprised over the past year that they haven't already done so, it would at least distance the company from the less-than-stellar reputation of the Venture.