Pretty much everyone here knows Motorola has said by the end of Q2, and that's what we expect. But given the constant flow of rumors that haven't panned out over the past few months, it isn't pessimistic to not put much faith in things that are just more rumors. It's realistic. The link in the first post quotes a source at Verizon. Well, pretty much all of the other rumors have quoted sources or leaks from Verizon too. The only things that really matter are official statements along with the start of an ICS soak test.
Those "pessimistic" people you're referring to have been through these types of updates time after time, and they know that no one should be getting too excited about rumors because most often, they don't pan out. Again, that's not being pessimistic, that's being realistic based off experience. Motorola says by the end of Q2, so that's what we're banking on. Until something else that's official comes along to support or alter that, everything else is a just rumor and should be treated as such.