NBA 2K11 and NBA Live 11 will both simultaneously be released on October 5th, 2010. There have also been rumors via Pastapadre that NBA Jam for the Nintendo Wii could also be released that day.
Usually, the two main basketball games have been either released on the same day or a week apart at the end of September or beginning of October so this is nothing new.
However, with the possible release of NBA Jam on Nintendo Wii by EA on the same day, the week could be dominated by NBA video game publicity and news. There will obviously be reviews of all the games at the same time and we'll see if these games can create buzz with the potential domination of the gaming headlines for a week.
The NBA games have not been that innovative recently though NBA Live is on the upswing. However, there have rumors of potential cancellation for the series, so this may be a make or break year. The 2K series has always been loved by critics and consumers alike but has remained stagnant for the last couple of years. NBA Jam is the wild card, as this is it's return year. It was a beloved franchise in the early 90s but is only being made for the Wii.
Sales aren't expected to be cannibalized simply because NBA Live isn't releasing on the Wii as it's just being replaced by Jam.
Check back in the fall for reviews and news for these upcoming titles.