depending on the adobe app, nvidia cards or amd cards will do differently
for houdini, assuming that the drivers work steadily for you, the 7970 will win as the gtx 600 line was built as a graphics card before a compute card(the fermi based 500 series is a better computer than the 600 series) as houdini is opencl based
for maya, i would think nvidia has an advantage, but i wouldn't know.
Considering you have an i7-3770K I assume you could be doing a fair amount of graphical work. And for that, the 7970 is the clear winner. In gaming performance, the 670 actually edges out the 7970 in 1920x1080 but for rendering and playing on higher res, the extra gig of Vram comes in handy.
Autodesk Maya= 7970 advantage(had to google comparisons)
Houdini= 7970 advantage
Adobe Suite= generally nvidia advantage to some extent, latest version of photoshop is working on larger opencl support.