More than 1GHz per core, and now ARM has two and four core options. This is tracking my predictions from a few years ago quite well. The google Nexus One has a 1GHz ARM CPU with 512MB RAM. I expect that the rumored Apple tablet or iSlate is more likely to be a big iPhone than a small MacBook, so it would make sense for it to use a multi-core ARM and a Gigabyte or so of memory. This gives vendors a nice way to stratify their product, for example, Apple could support multi-core and background/multiple running apps in iPhone OS 4, release a two-core tablet now, then upgrade the iPhone to have a two core high end option in the summer, and push the tablet to have a four core high end option. If Apple doesn't, then the Android vendors will.
My other prediction for 2010 (that I made in early 2008) was that as ARM goes up market, Intel will come down-market to lower power consumption. So later in 2010 we may see Android based tablets and phones that use Intel Atom variants going head to head with ARM, as well as running more generic laptop derived operating systems.
My millicomputing update ignite talk wasn't showing any text on the slides on slideshare, so I just re-loaded it.