It's a magazine format, simply a collection of VT
, live links, a segment on how to make something with a washing-up bottle and some sticky back plastic, occasionally followed up with some music and signing off.
This is nothing that any other network can do under a different name. It's not a gameshow or a package that can be sold. The difference with TOTP was that had a format to sell, which was adaptable to the local market and content wise it drove itself - run down the top 20, get some artists or their videos in based on that top 20, get live performance, get an audience in to dance and Bob's your uncle.
Blue Peter is essentially British in its format, and while it has had to reinvent itself and move with the times, it has been threatened with the axe many times over the years, plus its had own share of controversy as well. I believe it may be struggling ratings wise on the CBBC Channel too and has been since it was moved from BBC One.
A Blue Peter type format on an American network such as Nickelodeon wouldn't work. You've presumably seen modern day Nickelodeon live action shows where a bunch of weird characters don't talk, they just shout at each other on some garish set in equally garish clothes working on some strange story against a surreal plot... Even archive Nick stuff is more of the same, just not in widescreen/HD.