Halo 3 ODST ending confused?

[gamerfreak4949]

ok, i was talking with my friend about this, and he asked me if i saw the ending after the credits with Johnson, and i had not yet. He told me it was disappointing, and I have now just seen it. I do not know why it is disappointing, can someone maybe explain this to me, or even give me a synopsis of what it meant. I have not played halo 1 or 2, so if there is backround there that i need to know, please tell me. Yeah i know im lame for not playing campaign of halo 1 & 2, but w/e.

 

[WinterStarblade]

well it was confusing because in the Halo 3 game, Johnson supposedly died. but you see him talking to the alien at the end which makes it confusing. now, it COULD mean that Johnson didnt actually die but...
well i dont see how he thinks its disappointing. to me its just confusing.
and yes theres an actual Halo 3 game, not just ODST.

 

[??Arc??]

ODST takes place IN BETWEEN 2 and 3. Johnson is still alive of course .