Open Format?
To honest i can't see them using .OD* files of any format. The software services industry as a whole is more than a little wary of Open Source anything. These are the 'experts' that the people developing the document archive will turn to for advice. In my experience large software services companies have too many tie-ins with Microsoft for them not to recommend .doc (or whatever MS decided to call their next format). Failing that they will opt for .pdf, because "it's free". They invariably fail to mention (or possibly don't know?) that .OD* file readers and editors are also available for free.
Looking on my personal in the past most service suppliers are more concerned about getting their sales percentage from MS then delivering a Good Enough product to the end user. I've yet to find a normal secretary/receptionist that needs anything more OOWriter and Calc (some user's do need the macro functions of Excel though). However, if you even ask a sales guy he'll usually go pale and stutter about how MS product is so superior.