JavaOS this is just an evolution of scope of Android; a thin client (embedded client) with Web 2.0 interfacing (or SaaS) with each thread isolated from each other (for security) interfacing with Google services where profit lies in support, profiling, and targeted advertising.

It will be build on tons of existing open source software and technology, and nothing stops Nokia making Maemo interface with Ovi. If Ovi is competitive with such service while hosted in EU instead of US that is a big plus for me. However, this opens door for collaboration on other fronts. Nothing stops Google contributing to existing (sub)projects of Maemo; e.g. FreeDesktop.org standards.

IOW, it is not big (its an evolution to existing process, and the outcome will determine its effect on market), and it does not compete with Microsoft Windows clients (yet) in the way some media tend to report because Microsoft Windows is targetted at different hardware (client-wise: desktops, workstations, laptops), has different purposes, and has a bigger software ecosystem. Perhaps it will compete a bit with some Windows thin clients, but anyone still using Windows for thin clients is burning a lot of money into nothingness.

What might be big or not is Google's contributions to the FOSS ecosystem. That I see as part of the effect/outcome. So, we will see.