I love our Aldi. Clean. Wonderful staff. Great prices.
As one with a family member in the food industry, generics/store brands are generally made by some brand name company or another. Last I heard, Del Monte was their canned fruit and veggie supplier and Malt O Meal makes at least some of their cereals. You get an idea of who makes their store brands based on their "special purchase" items.
Consistently low prices on basics like flour, sugar, milk, eggs, oil, powdered milk.

Ours has great produce. Pretty good regular prices, but the weekly specials are great. I got one-pound cartons of strawberries there last week for $.99 each. (I just wish they had green leaf lettuce in addition to the iceberg and romaine.)
Ours takes debit cards in addition to cash (not credit).
BYOBags or you can collect the empty boxes as you shop or buy bags. Ours charges $.04 for paper and $.10 for a pretty good sized plastic one. (I've also just put my groceries in the trunk without bags.)
I keep a quarter in my car since I go to our Aldi's so often. The kids fight over turns to put the quarter in the lock.
I love it that they are adding more "Fit and Active" products with their regular line. (ie reduced fat generic wheat thins,snackwells, yogurt, etc.)