Thanks! It was only in the past several months that an atari 2600 emulator with the necessary features for making TAS's (BizHawk) became available. You may have noticed the tasvideos atari section has a "wishlist" thread, if you'd like to post suggestions:
http://tasvideos.org/forum/viewtopic.php?t=13374
I was interested to read on this forum players reporting having actually beaten River Raid, and that it took about 3.5 hours. Based on the 100k TAS, a million point effort would be just over 80 minutes.