So, Dan Houser confirmed 2 times that this is not a new Era. He said that there won't be returns as big as Niko or even Packie, but we will see some as Easter Eggs.

I saw that Wikipedia already changed the template, but some "smart" guy reverted it. BTW, you can check the article here:

IGN: GTA V: Burning Questions Answered

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Will we see characters from GTA IV show up in GTA V?

Packie's not in it. There may be the odd... They tend to be very small. The problem is that... You touched on this earlier. Because of a lot of the choices... We've never had a game where we've annihilated so much of the cast. I loved Roman, but he may or may not be dead depending on what choices you made. It would be difficult to bring him back.

So many of them were killed that we didn't really have a large amount of the main cast left over. There may or may not be a few guest appearances. Some really subtle ones for people to find. Little Easter eggs for people.

I always thought this is a single era. Why most of you believed it's a new one?