Externally the P150 is virtually identical to the 5MP DSC-P100, the only difference being the new brushed metal panel running across the front of the camera. Aside from the power (on/off) and shutter release buttons, which sit on the top of the thin body, the cameras controls are all on the rear plate, to the right of the 1.8" LCD. The lens retracts fully into the body when powered down, meaning the P150 is truly pocketable. The all-metal body exudes quality, and feels remarkably solid in the hand. All the buttons and switches are metal too - mostly chrome - giving the camera a slightly more serious feel than appearances might suggest.

In your hand

It may not look it, but the P150 handles really well. At 147g it is just heavy enough to feel solid and stable, and the lack of any grip on the front of the camera is offset by a small 'thumb grip' on the far right of the rear panel. This means it's perfectly safe to shoot one-handed, though I personally found the zoom a lot easier to operate if i supported the P150 with my left hand when shooting. The camera feels well balanced, but a word of caution; the lens is on the far left (looking from the back), and your hand is on the far right. This means camera shake is an ever-present threat when shooting single-handedly (a small movement of your hand can mean a big movement of the lens). We saw this in some of our quickly 'grabbed' shots at speeds as high as 1/200 second.

Body elements

The combined battery/Memory Stick compartment sits under a sturdy spring-hinged 'slide out and swing open' door. Both battery and card click into place, so no danger of losing one when changing the other. The P150 accepts Memory Stick and PRO cards (PRO cards are faster and offer higher capacities - up to 1GB). Battery life from the Li-Ion cell (320 shots/160 minutes according to Sony, using CIPA standard testing) is excellent.
The InfoLITHIUM battery is charged in-camera using the supplied mains adapter. This plugs into a small proprietary socket under a flap in the battery/card compartment cover. It's a minor complaint, but the mains adapter is the most difficult to get into the hole I've ever come across. It has to go in the right way, but the lack of a distinct marking on the plug to show the correct orientation makes charging the battery a very annoying affair. Good job you don't have to do it too often!
The small flash is a little underpowered (a quoted range 3.5m), which is perhaps why Sony sells an optional bolt-on slave flash unit. The red-eye reduction (using a burst of pre-flashes) has to be turned on and off via the setup menu, which is fiddly, but you do at least get a slow synch function and a three-step output level control (-, normal, +). For social snaps of small groups or a little fill-flash it's fine, but don't expect miracles.
The P150 inherits the excellent 38-114mm equivalent 3x Carl Zeiss Vario-Tessar lens from the P100. The F2.8 to 5.2 aperture is nice and bright at the wide end, but - inevitably in such a small unit - is less useful at the long end of the range, which means slower shutter speeds or increasing the CCD sensitivity. The lens retracts fully (and very quickly) into the camera body completely when not in use, and can be extended with various Sony wide and tele adapters, and filter kits.
The combined data (USB) and audio/video (AV) port sits on the base of the unit, near enough to the tripod bush to disallow its use when the camera is tripod-mounted. The connector is so placed to slot into the optional 'Cyber-shot Station' - a camera dock for easy image transfer and battery charging.
The 1.8 inch anti-reflective screen boasts a healthy 134,000 pixels, so is nice and clear. It's also bright and has a high refresh rate, so the preview image is very smooth. On the downside it is nigh on impossible to see properly in very bright direct light (despite Sony's claims), but is - to be fair - better than many in this respect. It does work well in low light, but - unusually - only automatically 'gains up' (brightens) when you actually half press the shutter and activate the AF illuminator.
The optical viewfinder is not that bad actually. Sure, it only shows around 85% of the scene, is too small and isn't even that clear, but it is at least usable, and near enough to the lens to avoid parallax errors in most normal shooting circumstances. Three LEDs indicate movie recording (top, red), focus status (middle, green) and flash status (bottom, yellow).
The main mode dial - the P150 has four main shooting modes; auto, program (fully automatic but with many more menu options), full manual and scene (subject mode). The other positions on the dial are for movie mode, setup and playback.
The remaining controls are clustered around the ubiquitous four-way controller on the rear of the camera.
There are only two buttons on the top of the P150; the main power switch and the chrome shutter release.