Well, my PocketBook 360 arrived in the mail yesterday, and I owe a big "thank you" and maybe a drink to everyone who talked me into it.
1. I love the ease of the SD card expansion - the spring mechanism works perfectly (unlike my Cowon MP3 player where you can't get the card out without tweezers and divine intervention). I don't know where this "you can store thousands of books on a 2GB device" meme comes from, but my library is 900 books at 3.5GB and growing, so being able to use a 32GB card to store my library is wonderful. I have four eReaders now (phone + nook + nook color + pocketbook) and I literally receive new eBooks on a daily basis and I really cannot be arsed to hook up four devices to my computer weekly to keep everything in sync - SO much easier to just have the entire library on a single card that can be slapped into a reader before heading out the door!!
2. I love the light plastic casing. The pocketbook fits in my back pocket (Exactly What It Says On The Tin!) and it's so light that my wrists don't tire. I didn't like the relative heaviness of some of the metal-cased eReaders, so this is perfect.
3. I like the screen just fine. I've never really seen the big deal with Pearl screens - there are some very light "ghosting" issues with the PocketBook, but the screen refreshes frequently enough that it's not been a problem. Speaking of:
4. Customization! Love being able to set screen refresh rate and time out behavior and everything else so easily. Love, love, LOVE being able to use different stock readers (and new downloaded readers!) for different book types. Love the fact that so many formats are accepted. (Conversion simply doesn't cut it sometimes.) LOVE being able to map different behavior to different buttons - it's like the makers KNEW I was a control freak with buttons. Love feeling like the device works for me instead of me for it.
5. This may be a minority opinion, but I actually prefer that it's not touchscreen. I don't really need touch screen for a simple reading device - I don't like swiping my fingers across the device to turn a page when a single button press is more minimal movement for me. And while the stylus for notes is nice, not being able to export them (that I could find, anyway) makes them useless to me, and I'd always be afraid of losing the stylus, I suspect. I'll take my notes on my Nook Color / Phone via the Moon+ app with export.
6. Price-wise, in my area, the PocketBook 360 and the Sony PRS 350 were identical. So there's that.
Anyway, thank you all again - I can definitely see why this device has a strong following, and it's perfect for my needs. I do appreciate all the help.