Well, I'm a bit bummed about the lack of a turtle.
I agree with Meepo that it would be a bizarre world to live on (from our perspective, the native inhabitants would thing nothing of it). Is this place more or less a perfect hemisphere? (as opposed to a more shallow or deep chalice?)
Regardless, if you live near the rim, your sky is about half, vast expanse of clouds and minute terrain. The other half is black, starry night.
But when the sun goes out, half the sky is a starless black expanse, perhaps with a few tiny dots of light if there are cities advanced enough to make use of torch lighted streets at night.
Actually, a rather large question about how the world appears is whether the entire cup is full of air. If you had an indefinite source of flight, could you fly all the way to the sun with air to breathe all the while? If so, then seeing any other part of the cup from a given point on the "ground" will be impossible due to the atmosphere.
I won't get into the issue about how that much atmosphere would generate some hellish air pressures at sea level, because it's magic.
Another big question is, "What happens if you walk up to the rim?" Can you fall over the edge and out into space? Is there a wall around the inside edge.
Then again, maybe you don't really care about all this minutae. But if you do, you might want to look up some information on Dyson Spheres, because your world is basically half of one. I'd also highly recommend reading Larry Niven's
Ringworld and
Ringworld Engineers. They're fun and contain a lot of information about an unusually shaped world.
