I still crave for a really nice word processor, spreadsheet, and easy database app (in the style of Access). I've always found *Office a bit rough around the edges.
My partner recently brought home an iPad from work. Word failed to play well with other (MS Word) Office documents, so file exchange and formats are still a complete pain in the neck. I will be using plain text until something better comes along.
The word processor and spreadsheet are rudimentary and the OOXML compatibility is terrible.
My favourite new feature in LibreOffice is the Google Drive integration (a first-class feature in LO 5.1). Because sometimes I need a proper bloody word processor or to read an OOXML doc someone's sent me.
LO Online will be proper LO at the back end, so will be that word processor etc.
The current core market for office productivity suites are business, followed by consumer. And I'd bet only a very small minority of those are sticking with plain text files until something better comes along.
Didn't RTF coma along a couple of decades ago?