We've always advised a degree of cynicism whenever a phone or tablet manufacturer proclaims how many apps it has available. Here's another reminder why that principle matters: it looks like 10 per cent of the apps available for Surface RT are all variants on a single app from a single developer.
At WP Down Under, Sheeds notes that of the 56,000 apps available for Windows RT, more than 10 per cent are from a single developer, Fanfinity. That number has been going up rapidly, and the apps (which are 'fan' apps for musicians) appear to be essentially the same code, with the only difference being the performer involved.
The reality is that most consumers will only use a handful of apps on any platform, and sheer volume doesn't help. I'd use my Surface RT a lot more if it had Chrome on it, but that seems unlikely.