I think that since this is an investigation into a missing person, it is a big deal to find some belongings of that missing person.
Also, there has been a huge public interest for Samantha allegedly being murdered.
Yes it is a big deal to find something belonging to Samantha, especially her phone that was still in good working order and may have held vital information.
And yes there is a lot of interest in her disappearance.
I would say there is even more interest and police have spent possibly 25 times the amount of money on trying to find fugitive Dezi Freeman.
But have they revealed anything about what they have found after a month of searching for Freeman in the bush and all over the place...no not a word.
And that's because it is vital in finding Freeman that information isn't given to the public that they may be close to finding him.
But in Samantha's case and this is MOO they made a big song and dance about finding the phone, what it was and that it was working just fine, not to inform the public but to put pressure on anyone involved in Samantha's disappearance in the hope they will make a mistake like camper killer Greg Lynn did in vaguely similar circumstances.
I agree with police they have to attempt to outsmart criminals and I believe the phone business was one of those attempts.
I could be wrong and finding the phone as you say was a big deal and so let everyone know it was found.
Or I could be right and they already knew nothing was on the phone and it was simply a ploy to either extract a confession from someone they had in custody, or to get someone who helped in her disappearance to come out into the open.
One of the very few brilliant bits of police work I've heard about was when they caught Brett Peter Cowan in a sting. The only criticism I would make on that operation was that it was almost a decade after Cowan murdered a 13 year old boy and from his history Cowan should have been under suspicion much earlier.