The best way to answer your first question is to look in their job listings, or in this case their blog. This is something I learned from PG's story of looking

The best way to answer your first question is to look in their job listings, or in this case their blog. This is something I learned from PG's story of looking at competitors' job listings in his Viaweb days. They want (or wanted) someone with "Heavy experience with C# and/or .NET in general". That makes me think Flash isn't the only important technology for them.