The YN300W monolights have Canon Optic Wireless slave function built in, as well as being compatible with the popular YN-622C TTL radio trigger system, and just released YN-622C-TX transmitter units.
This means the YN300W can be used together with regular TTL speedlites, all using the same radio trigger system, and providing TTL metering and remote manual power control. As well as features like Second Curtain Sync, and Flash Exposure Bracketing.
The YN300W are mains powered studio lights, with no mention of a portable battery pack and inverted option from YongNuo as yet.
There is also no mention of a HSS (High Speed Sync) function with the YN300W. Though the Long Duration Sync method of higher sync speeds may be possible to some degree, as the compatible YN-622C-TX transmitter has an adjustable Supersync feature.