I realized that they cut the price off of Persona games on PSN by 50% from this NeoGAF thread, so I thought I'd give you guys a heads up for anyone interested. All of these can be played on the Vita with the exception of FES.
Shin Megami Tensei: Persona (now: $9.99 original price: $19.99)
Shin Megami Tensei: Persona 2: Innocent Sin (now: $14.99 original price: $29.99)
Shin Megami Tensei: Persona 3: FES (now: $4.99 original price: $9.99)
Shin Megami Tensei: Persona 3 Portable (now: $9.99 original price: $19.99)
I already own all of them and have played them on my Vita, but I only own the disc version of FES so I might as well get the downloadable version for the PS3.
When Persona 4 Golden releases later this month, there'll only be one gaping hole before all mainline Persona games can be played on the Vita in North America... Hopefully Atlus will rectify that.