Removable battery? Meh... Replaceable batteries FTW!
Don't really care if the battery is removable or not. What I would like to see is a battery that is easily *replaceable* when it reaches the end of life, without having to crack the case open with specialist tools and/or send it back to a manufacturer.
Your battery could lose around 25% of capacity within 9 months or so of charge-discharge cycles, and I tend to find after about 18 months that it's annoying me enough to look at doing something about it. I'd like the option to get a new, genuine battery fitted that wouldn't cost half the price of a new phone to sort out.
Of course, the irony of owning a Samsung phone and wanting a genuine battery is not lost on me at this point...