From the CSGO FAQ
Q: Can I buy items that will affect gameplay and give me an advantage?
A: No. All of the items are purely cosmetic.
Q: Does this mean CS:GO is free to play now?
A: No. The Arms Deal Update is aimed at rewarding the wide spectrum of players who have already purchased CS:GO -- from players looking for new ways to express themselves in-game, to CS:GO’s competitive community getting well-deserved visibility and bigger rewards for their high level of skill.
I wouldn't be too worried about the guns to be honest, they're going to be skins that everyone can see.
F2P isn't happening, just public models and skins.
Knowing Gamebanana community, they will just make all the skins default for everyone to use if the camos get annoying.