PDF rendering - how much is iPad2 faster than iPad?
According to iPad vs iPad2 Speed Test the iPad2 is about 20% faster than the original iPad both overall and for PDF rendering:



From the article:


  Across the board, we're seeing approximately a 20% average speedup in rendering PDF content. Complex vector content such as maps and blueprints -- which places a heavier load on the graphics subsystem -- is getting the biggest boost, with improvements in the 22% - 32% range. High-resolution scans, which places more of an emphasis on disk I/O and memory, is seeing a more modest 8% - 19% improvement. Perhaps the most interesting improvement is in the multi-threading, where we're seeing speedup increases of up to 10% when doing drawing while other tasks (PDF processing in this case) are running at the same time.