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Nowadays most broadcasters either buy Sony or Panasonic cameras and decide that either XDCAM HD 422 or AVC Intra is going to be their main production format.
It totally makes sense to consider the camera preferences of your OB teams and the storage capacity your raw material is going to occupy in your post and in the archive, and these two points seem to be the main points influencing format decisions.

Yes, XDCAM HD 422 is a 50MBit format, and AVC Intra needs 100MBit for comparable image quality, that's why many people think that XDCAM HD 422 is more effecient and therefore the format to go for.

Yet, XDCAM HD 422 is NOT a constant bit rate (CBR) format per frame, as it is a long GOP format, where an i-frame takes up to roughly 120 MBit, while the following frames go down to around 30 MBit. This means that XDCAM HD 422 is a variable bit rate (VBR) format with roughly 50Mbit/s as average.
In opposite, AVC Intra IS an i-frame only format and has a constant bit rate, which allows to have simpler header structures and make it more effective in postproduction.

As i-frame only formats are much more effective in the post, most XDCAM HD 422 houses convert their XDCAM HD 422 footage to ProRes or some other i-frame only format before they edit it. This brings up new problems: the material in the post is already the second generation of the clips, and you don't want to send ProRes files into your archive, as it is not an SMPTE standard.

So probably you end up re-encoding your material to something else before you send it into your archive. This would at least be the third generation of your raw material. If you ever need to fetch this material from the archive and work on it again, quality will decrease with every new generation of your clips.
If instead you choose AVC Intra as your main production format, you can fetch it from the OB team and directly work on it in the post without re-encoding it.
You can even change the OP Atom structure to OP 1a (or vice versa) by simply rewrapping files without re-encoding, so you would still work on the first generation of your raw material.

AVC Intra is also more appropriate for the archive than ProRes is (though an open codec like in the famous BBC project would still be more preferable), so you might have an end-to-end workflow without ever generating more than a second generation of your material.

But now comes the really interesting part: Imagine you create two sequences in Final Cut Pro (or any other editor), one for XDCAM HD 422 material, one for AVC Intra material. If you only use hard cuts in your timeline, exporting the final clip from the AVC Intra project would simply copy all the i-frames from the source material into the new file and write a new header – no compression or re-encoding necessary.

If you do the same with your XDCAM HD 422 project, your editing application will need to re-encode parts of your sources, as your cuts will most probably be somewhere within long GOPs. As the first frame after a cut needs to be an i-frame, your application needs to calculate the content of the previously referencing frame and reference (and encode) the following frames of the GOP to the newly created i-frame. This way each cut can trigger a render operation for up to more than one second of source material. For each cut!

So even with hard cuts only you can generate a second generation clip with XDCAM HD 422 material, while AVC Intra material would still be first generation.

Though this should not be the only point to consider when you decide for your main production codec, I tend to think that choosing AVC Intra over XDCAM HD 422 can help you keeping image quality throughout your workflow high as you need to re-encode less.

AVC Intra on mielenkiintoinen formaatti, harmi vain että sen tuki on mm. ulosajojärjestelmissä suhteellisen rajallinen. Lue koko artikkeli täältä.