I try not to carry my leather bags in the rain, but sometimes I carry my black Coach leather tote if I have to carry many things. Since it's black and wasn't too expensive (from the outlets) I don't feel as bad about getting it a little wet. I have a light blue MBMJ bag that I brought out before and when it started raining the back got a little stained from my leather jacket + jeans.

So now I avoid bringing that one out even when there's the slightest hint of cloudy weather!
In your case, since you've treated it with repellent I guess it would be fine, though I really suggest not wearing dark denim and/or leather jacket like I did (especially in the rain), just in case your bag gets stained!
Lovely bag, btw, I really love the whole Kristin leather bag line!