HD or SD?
How many cameras?
Any other sources?
What's your plan for audio?
How do you plan to record?
Waht's the event and venue like?
What's the distribution method? to DVD? broadcast? webcast? live?
HD
4 or 5 cameras
Graphics will be done in post
portable mixer for audio, only 3 or 4 people speaking on lav's
Will record to HDcam deck or maybe hard drive
Location will be controllable
broadcast
Audio seems simple enough.
For video you need monitors and a video mixer.
Workign HD with the HVX, you are starting with analog HD component...
You can get a HD Component switcher, like the Edirol V-440HD ... however that will mean you'll need 3 carefully matched coax cables from each camera to carry the Component signal.
Or you can get a low end HD-SDI switcher, like the new offerings from Focus or the Panasonic AV-HS300G (my preferance). And a HD-Component to HD-SDI converter.
These converters are available either as a upgrade card to the HS300, or as an external unit from Focus: "MCSDI-1".
I haven't done a full price comparison. But for features I'd recomend the following:
Focus Component->SDI converters for each camera, then single HD-SDI cables into the Panny HS300 video mixer. That's the most versitile set-up.
As for monitoring. You will need a couple of HD monitors for Preview and Program out from the video mixer at a bare minimum. You'll probabaly want monitors for each camera's feed too - these will need to match the HD format that goes into your mixer so you can loop the signal to the monitors.
If you go to SDI at the cameras, then a HD multiviewer mike the Miranda Kaleido-Alto-HD could get all the signals looped through the Panny or smaller Focus (4 inputrs only) switcher and display them all on one HD monitor or (low cost) HDTV.