They're on track with their Mars mission program, and the side effect of the vehicles they're building - and predicted drop in kilogram-to-orbit price tag - will be opening up the whole cislunar space for industrialization. Think in-orbit mining, resource processing and manufacturing. Optimistically, the potential market will explode in size, and ultimately (say, in a century) will be greater than the whole economy of Earth today. So, if you're bullish on space exploration and exploitation, then SpaceX's market has no limit in sight.