Well it is a coding contest, but it's also up to your originality. The competitors have to code a game based on a special theme that will be revealed at the 28th April. So it's no real shmup development contest. But there are also shmups created and you might be interested to make a shmup or any other game for it.
If you are interested and want to register or want to get more infos, then please check: http://ludumdare.com/ludum/
Have fun.
