I think it depends a lot on the type of reduction you have as to whether you can sucessfully feed. I had a type of surgery which is called maxopexy which leaves the nipples intact but takes flesh out from underneath the nipple area and 'lifts' the boobs back up. I breastfeed my DD for a year, although supply was better on side was better than the other. My cousin had whoppers and she had her nipples removed and repositioned back on higher after removing a lot of breast tissue underneath (sorry for the graphics!). She found she couldn't do it.
I would encourgae your friend to talk to a lactation consultant (most hospitals have them), and find out what she can do before she gives birth. As much info as you can get is better. I went into determined to breastfeed and did not buy or consider getting anything ready for bottle feeding as I felt that I might cave in and give up. It was hard, I got mastitis (but lots of mums do regardless), very sore cracked nipples and my scars because sore from swelling and pressure. But after about 6 weeks my DD and I had got into a routine and I found it came quite easily.
