So basically...
Stick with .com (64% of the top 1000 websites use .com over other extensions).
Avoid domains with numbers (only 6% of the top 1000 websites use a number in their domain).
Domain length doesn't matter (54% of the top 1000 websites have 9 or more characters).
.com/.net/.org are still the top 3 of all extensions used (amongst the top 1000 websites).