Good point...the marketing of it bets on the following:

1. All you need to do is swap a barrel with your favorite .22 and you are good to go.
(problem is the barrels run $125+ and if you can buy a new gun for $169 (10/22) why bother with buying just the barrel. Some guns will also require gunsmithing to get the new barrel on or off...again more money.

2. It's supposed to be cheaper than the .17 HMR with not nearly the performance (2100 FPS with the same bullet). You can buy .17 HMR for like $8-9 a box...the MachII is supposed to sell for $9 a box which means $7 a box....my cost is just around $5 a box....I don't see the value.
But a lot of people are excited about it...