Thanks for trying out Sublime Text 3!
Sublime Text 3 is a paid upgrade from Sublime Text 2, and an upgrade will be required for use when 3.0 is released
Until then, please enjoy Sublime Text 3.
Why is it required? If I don't consider purchasing it, then does it means my Sublime Text 2 license will be expired? If you're making this upgrade mandatory, you should make it clear at the time everyone who is purchasing a license for Sublime Text 2. When I purchase mine all I'm told is Sublime Text 3 will be a paid upgrade. It didn't say the upgrade will be required, nor it say when the 3rd version is released.
I can afford the upgrade and I probably will, but I would be less disappointed in the dev if he just make the price $90 and the upgrade free