While there isn’t a complete list of titles that now work with the PS Vita, we do know the Crash and Spyro PS1 titles in the recent Flash Sale are compatible, with reports also showing Jeanne D’Arc, Metal Gear Solid: Portable Ops, Brave Story, Motorstorm: Arctic Edge, and Phantasy Star Portable 2 now work as well.
A tip to play classic PS1 games on PS Vita: Hold PS Button to bring up the system menu. Select Settings and assign buttons to Analog Sticks.
To play Spyro 1, I assigned R2 to “Right Analog Stick <” and L2 to “Right Analog Stick >”, so I can control the camera as I usually do.
It’s possible Sony will detail every game now Vita compatible in their weekly PlayStation Store update post later today, but in the meantime, feel free to let everyone in the comments know what games you’ve discovered that are now working on PS Vita.