It's not the fastest either maybe the iPad 2 would speed things up more than I think but I'm going to hold off for the iPad 3/4 to see if I can get some real speed gains
Don't know about Photosmith, but the latest version of PhotoRaw, which is iPad 2 optimized, is 2-3 times faster on the iPad 2. Not just because of the dual processor, but also because the iPad 2 has twice as much memory, which is really useful for raw conversions. The iPad 2 optimized version of PhotoRaw Lite, the free version, isn't out yet, but should be available round about the end of the week.
Sandy