If it seems odd that Reader should appear on the Desktop and not in the mobile version of Safari, we can only hope that it's being used as a test bed to first refine it based on feedback. The feature's unveiling was greeted with much kafuffle about the impact it might have on website visitor metrics, but as the visitor to a site, the ability to dismiss things you're not interested in brings a sense of empowerment - like a Flash blocker on steroids.
Even so, after the honeymoon we've found ourselves relying on Reader less, but it's useful for sites with headache-inducing typography and text that's spread across multiple pages. Reader recognises that, pulls it all together and reassembles it into one long piece, so you even get the whole caboodle in one click when you email or print a page. It's not perfect, though. For instance, sometimes it misinterprets linked Wikipedia entries and combines them.
Part of the lull in our use of Reader can be attributed to our reliance on services such as Instapaper to line up material for later consumption, and if you don't use something similar this could become an indispensable feature for your online research.
