I'll address a couple of points you missed (edit: but which you have addressed elsewhere in the thread - just wanted to gather it up in place rather than post 10 times):-

a. If putting a GPS tracker on my car* involves venturing onto my driveway during the night, then you're intruding on the curtilage of my dwelling. The fact that the mail carrier or meter reader is allowed to do so does not mean that I grant the police a free invite onto the easily accessible parts of my property. This is the basic issue that the Supreme Court will take up today.

* not that I actually have a car - a cunning anti-surveillance measure, if I say so myself

b. Even if I park my car on the street, shouldn't the police have to deal with economic scarcity like everyone else, and prioritize whether or not I am worthy of investigation? If technology as a matter of convenience is acceptable grounds for carrying out surveillance, why not require all cars to be fitted with GPS trackers that record their position and can be read out wirelessly by any passing cop who thinks he recognizes your car from a recent tip? If we don't want to force people to buy GPS devices, then why not make such GPS data automatically searchable? Google Latitude records all my movements, should the police have access to that without a warrant for reasons of convenience?

c. In any of these cases, should we mandate that the information be public? After all, if a crime is sufficiently interesting, the media will sue for access to all evidence or to broadcast the court proceedings on first amendment grounds (spurious ones if you ask me; I've soured on TV trials). Since the evidence will become public anyway, what interest does the individual have in keeping it private once the state has decided to inspect it? No jurisprudence says that you have any property interest in your privacy, and it's not hard to construct an argument for any given search being reasonable. I've seen the presence of raindrops on a moving vehicle at 3am offered and accepted as reasonable grounds for a search (which correct intuition helped to catch a murderer fleeing the scene of a crime, as it turned out).

d. If almost any search is reasonable and can become a matter of public record by default, is there not an argument that possession of a GPS device in a car or phone that is deliberately turned off, disabled, or left behind by the user constitutes circumstantial evidence of intent in criminal or even tort cases? As you know, the threshold for establishing intent or knowledge in criminal cases can be quite low if it's not the sole fact in question, and it's lower again in civil litigation. If I can demonstrate a pattern of GPS use on your part that is temporarily interrupted during a period overlapping the commission of a crime that was reasonably accessible from your last recorded location, isn't there a basis for suspecting that you wished to conceal your movements?

e. Even if a warrant is required for me to get hold of your phone records or gain access to the contents of your phone, doesn't the fact that I could snoop your phone use over your shoulder whenever you pull it out in public compromise any expectation of privacy that you have when operating your phone in public? In other words, if I approach you while using your phone and suddenly order you to hand it over for inspection on the grounds that I saw something which appeared suspicious to me on the screen, are you entitled to lock your phone by hitting the power button? After all, your phone was open to the world (in plain view), and that's why I noticed something suspicious about it. Your locking of the device would then seem to constitute interference with a lawful search...

Sure, I'm playing slippery-slope here, but these are all cognizable arguments and I have heard as much and more from various conservatives and police officers over the years. I'm rather conservative myself where jurisprudence is concerned, but GPS tracking strikes me as an active rather than a passive sort of surveillance, not least because it necessarily involves interference with property or person to plant the tracking device.