For the case of Wikimania 2013, we did outsource video-recording and streaming to SocRec, a local video journalism group. The streamed videos are still available on the SocRec website, and they left a HDD with all the footage at the end of Wikimania.
A 3-9 month delay between the end of Wikimania and the uploading of videos has been the case for many past Wikimanias. One of the main concerns is cost: it would be considerably more expensive to contract the filming company to do all the post-production.
If enough Wikimaniacs think it is important to have the videos available promptly, then it may be an idea for WMF to set aside funding for someone to work in the WMF datacenter after Wikimania to process and upload the videos... (I say in the datacenter rather than as part of the recording contract, because as many WM13 attendees have found, average upload speed from HK to WMF servers is less than 10kB/s)