I got two mails from a new source (Thanks!) that seems to know a lot about the upcoming new NEX products. According to him Sony will:

1) release a NEX-4 (16 Mio, 1080p Video) in May 2011 (its the successor of NEX-3). It will be available as a kit (no body only).
2) The successor of the NEX-5 is coming later, together with…
3) the NEX-7 (24 Mio) in October. The NEX-7 will have the the same sensor like A77 a lot of “mechanical” controls and superb build quality. The cost of nex7 together with 18-55 lens is ~1200€-1250€.
4) New lenses this year: 1,7/24 ZEISS, 3,5/30 Macro, 1,8/50 and 4-5,6/55-200.

Reminder (SR = Sonyrumor):
SR1=probably fake rumor
SR2=rumor from unknown sources
SR3=50% chance it is correct
SR4=rumor from known sources (60-80% the rumor is correct)
SR5=almost certainly correct!