Don't worry, I'm using <em> and <strong>!

OK, have tried it in getting_started1.findpod_ex1. The translation now reads:

'Unlike most social networking sites, which have a central hub of computers on which everyone’s data are stored, we can’t give you one specific link and say: sign up here. diaspora* is different from those networks in that it is <em>decentralized</em>, with many different points of access. Before getting started, you’ll have to decide which diaspora* provider you want to sign up to. We call these providers “pods.”'

And the <em></em> codes are rendered as text in the page, rather than being treated as HTML code.