The Nexus One is listed as supporting a maximum of 32GB on an SDCard.Based on  reports here and elsewhere, I took out my 32GB card and put in this 64GB card and powered up the phone.The phone reported that the card was defective in a notification.I pulled down the notifications and tapped the notification that issued that report.  It offered to format the card.I would note that I have Clockwork Recovery and the ROM Manager app installed on my rooted (CM7, Android 2.3) N1.After tapping the notification, the phone formatted the card.  All went well.  Since I had neglected to move my RootExplorer file manager off the SD card prior to putting in the new card, I was not able to check directly on the phonethat the entire 64GB was available.  But, as it turned out, it was.While doing the above, I had been using Winzip to make a copy of the contents of my 32GB card to my PC (using a USB adapter).  When that completed,I powered down the phone and put the new 64GB card in the PC using the Micro SD adapter that came with that card and a USB adapter for that adapter.It showed about 60GB (the usual for a 64GB card, I guess).Interestingly, some files (mainly folders) related to clockworkmod had been placed on the SD card during formatting, which shows where the formatting codeprobably came from.  Take note: if you do *not* have ROM Manager / Clockworkmod on your phone, your mileage may very well vary.  If you have root, I would suggest obtainingROM Manager from Google Play prior to doing the above.  Anyway, I just deleted those files so that they wouldn't conflict with any of the old files I was aboutto copy.I then unzipped the saved contents of my old card onto the new card.Then, I put the new card in the N1 and powered it up.  It worked perfectly, right away.Root Explorer showed about 60GB of capacity (of which about 30 was used by me - I really needed this card!).Tried out Spotify Premium and it played fine from saved files that had been on the old card and were now transferred to the new card.  Other thanRoot Explorer, haven't tried any other apps yet, but am expecting good news based on the experience thus far!I tried a full backup using ROM Manager and it apparently worked without incident.So, based on the above, I would recommend this card for the Nexus One!  What a break to get another 30 GB on an aging phonethat is nonetheless still one of the best phones ever.Caveat: Keep in mind that I just unwrapped this thing and have used it for all of two hours.