Early success with a 32gb-insertion
It was a hassle with which Att and Samsung could not help, but I eventually succeeded in installing a 32gb card which is working on its fifth day. It is a Sandisk card I ordered from Amazon for $47 ("bulk" packaging still available from Blue Proton, fulfilled by Amazon). The packaging was pretty normal Sandisk -one of those impossible-to-open cardboard & plastic 2" by 4" packages you may see hanging on a store display. No adapter or anything else.
My first card-insertion attempts Thursday evening failed. I followed the instructions on pp. 11-13 of the user guide. It was the first card installed and I had not read the warnings on p. 10, nor here, before I ordered the card. I was getting the home page after the 3-key hard-setting instead of the "Start-up Wizard screen", which I never did see. I also kept seeing the same total-storage on the About screen after each attempt. I called Att first and got no help. When I asked for a higher-up tech level, the same person came back to say that I was to call "the manufacturer" and she gave me a number. She also advised me to try going to the store in the morning, though did drop in passing, the idea of reformattng or restoring the operating system, but when I said I was open to any good ideas, she said I really should just go to the store for such or other assistance. Samsung advised me that they were only certifying a certain 8 gb card -which I ignored because not being able to use a 32 card is probably a deal-breaker for me. After hanging up, I made several more 3-key attempts before I decided to go ahead and reformat the operating system. After all, if the store had also failed and did not have a 32gb-solution for me, I was ready to leave the phone. The OS restore or re-format did it! Again, I never saw the Wizard screen, but after my first 3-key format attempt following the reset, although all I still got was the home screen, I went to the About page and saw the total storage had jumped to 36+. I then connected it to my Toshiba Portege as a clean initial install on a fresh Zune re-install. It went through the Focus installation and two WP7 updates without a hitch. I then draggged my Zune collection to the phone.
I can only report at this time that all functions seem to be running fine including playing music in shuffle mode from throughout the 30gb collection I transferred. I'm running a battery-drain test this afternoon with the musc player running in Airplane Mode but wi-fi connected. The fidelity is nearly as beautiful as what I get on the ZuneHD. I've read reports that 32gb installs have stopped working, so I'm going to hold off on a celebration and recommendation.