My own experience: yesterday I've bought a 8Gb Sandisk micro-SD and a PNY micro-to-mini adapter. No problem in my N800 (using a mini-to-SD adapter). Today my N810 arrived by UPS: I've put the micro-SD and its adapter into it and... it works
What is sure is that each parts are very small and it's not always easy to put the micro-SD into the adapter, so some may be encounter problems when all parts are not perfectly aligned... just my opinion...