The free 3G addition would be make the new device a strong competitor against Apple's rapid increase into handheld gaming market. As of today, the DS Lite, DSi and DSi LL are limited to 802.11b Wi-Fi and have just a small footprint online.
"An always-available Internet connection would simplify app downloads and Internet-based play and give the DS an edge over the iPod's limitation to short-range wireless as well as the iPhone's expensive long-term cost."
There are a limited number of games supporting an online component and the DSiWare mobile app and game store carrying only a small number of titles but, none the less this would be a hot feature.