The first competitive session of the season can tell you so much about prospects for the teams' ambitious new machines in 2015.
BBC Sport gives you the lowdown on who is enjoying the Melbourne sunshine and who might want to throw themselves into Albert Park lake.
It is, of course, early days, but it would appear as if last year's dominant world champions are even further ahead of their rivals this season than in 2014.
Hamilton was 1.4 seconds clear of the first non-Mercedes, and if the gap from his German team-mate Nico Rosberg to Williams's Felipe Massa was only 0.8secs, that was more attributable to the German making a bit of a hash of qualifying than anything else.
The unpredictable windy conditions - and a wind direction that had flipped around 180 degrees after final practice - made qualifying perfect for Hamilton's gifts.
|Live coverage on BBC Sport website from 03:30 GMT and BBC Radio 5 live from 04:30 GMT. Watch highlights at 13:15 GMT, Sunday, on BBC One|
The challengers, such as they are
The battle between Williams and Ferrari to be best of the rest was expected to be close, and so it proved, with just 0.072 seconds separating Williams's Felipe Massa in third, and Ferrari's Sebastian Vettel and Kimi Raikkonen in fourth and fifth. It will take more time to discern whether Ferrari are genuinely on the up, but for now the racing between them and Williams looks likely to be just as intense as that between Hamilton and Rosberg.
Renault in trouble
Red Bull have had a chastening weekend, and typically team bosses Christian Horner and Helmut Marko have not tried to hide their dissatisfaction with engine partner Renault. Renault's engine is worse than it was last season - no more powerful, just as unreliable and with worse driveability.
"I have no idea how they have managed to mess it up so badly," Horner told BBC Sport. Except the word he used was rather less polite than "mess".
So fractured had been Red Bull's build-up to qualifying that new driver Daniil Kvyat said he was "guessing not driving" as he fought for grid positions. The Russian driver was 0.4secs off his team-mate Australian Daniel Ricciardo, who was in at least as bad a position. Kvyat finished qualifying down in 13th position.
As if that was not bad enough, Red Bull will face awkward questions about the comparison with their junior team Toro Rosso, who operate on less than half the budget. Not only did the engines run with no problems in the Toro Rosso, but their rookie driver Carlos Sainz Jr was highly impressive in qualifying - just one place behind Ricciardo and within 0.2secs of the Australian, who took seventh spot.
All of which raises the possibility that Toro Rosso's tiny team under well-regarded technical director James Key has designed a better car than the legendary Adrian Newey. Which would be a bit embarrassing if it turned out to be true.
Looking up at Lotus
That Lotus were slightly disappointed with ninth and 10th places on the grid says a lot about how far they have come in 12 months, after designing a dog of a car in 2014. Still, solid points were the aim coming into this race, and that looks very much on the cards, which would be a good start to a season that should be a vast improvement on last year.
Uncertainty at Sauber
After a tumultuous weekend, including missing all of first practice as a result of the contractual dispute with former reserve driver Giedo van der Garde, 11th place on the grid has to count as a triumph for Sauber and their driver Felipe Nasr. Whether the Brazilian will be in the car at the next race, though, is a different question; as is who will be running the team.
It would appear there was a lot more to the Van der Garde situation than a mere argument over a driver contract. The whispers in the paddock were that the ownership of financially troubled Sauber is at stake, and that the former Caterham, HRT and Midland boss Colin Kolles may be in the background. Things will become clearer in the next few days, it seems.
Force India may not have problems as serious as Sauber's, but they are clearly suffering from the cash-flow issues that led to them only doing two-and-a-half days of testing with their new car.
McLaren - five seconds behind Mercedes. FIVE
That number is probably around the equivalent of what McLaren managed in 12 days of pre-season testing. It was clear long ago that they were off the pace, the problems almost entirely down to their new Honda engine, but few were expecting it to be this bad.
Three seconds on paper off the pace of Mercedes in the first qualifying session (Q1), after which McLaren drivers Jenson Button and Kevin Magnussen were eliminated, equated to about four seconds once the fact that McLaren were on the soft tyre and Mercedes on the medium at the time, was taken into account.
Add in that Mercedes will have turned up their engine between Q1 and Q3 and the real deficit between McLaren and Mercedes is in the region of five seconds.
Button and the team bosses continue to talk a good game about the potential of their new car, as long as the engine problems can be sorted out. But it is a big "if".
|Chief F1 writer Andrew Benson on Australian GP|
|"It's hard to think of a better place to start the season than Melbourne and somehow it would not seem right if the opener was anywhere else.|
|It's an awfully long way to go for a motor race but the reward is a vibrant, fun city, a view of Port Phillip Bay, and one of the loveliest venues on the calendar.|
|The autumn leaves are just starting to fall in Albert Park when Formula 1 pops by, the air is scented by pine and eucalyptus and the atmosphere crackles with anticipation of the season ahead.|
|And the track, a mix of street and road circuit, with walls ever close, pretty much guarantees action of one kind or another."|