In terms of performance the A330 is nothing too special. Like most DSLRs it starts up extremely quickly in about a quarter of a second, and shuts down again just as fast, although it does briefly run the sensor cleaning system on power-off. In terms of shooting speed, in single-shot mode it is pleasantly quick to use. The nine-point AF system is nice and fast, and with the focus points well spread over the frame it copes well with off-centre subjects. It focuses well in low light, using a pulsed flash as an AF assist lamp. However the pop-up flash itself is surprisingly underpowered and doesn't fill the corners of the frame in a normal size living room.
In continuous shooting mode the A330 isn't going to break any world records. It can maintain 1.25fps, which is pretty slow by comparison to most of its rivals, but it can maintain the same speed in Raw + JPEG mode and also in live view mode, which is more than some others can claim.
Picture quality is pretty much indistinguishable from any of Sony's previous 10.2MP DSLRs, which is to say that it's very good under most circumstances. The built-in sensor-shift image stabilisation system provides a reliable two to three stops of extra hand-held stability, which means sharp hand-held pictures even at around 1/20th of a second. Exposure metering is generally accurate and copes well with backlighting, and the D-Range Optimiser helps with very high contrast situations. Colour rendition is also very good, but where the camera has real problems is with image noise. Even at 400 ISO there is visible noise and loss of detail in the darker areas, and at 800 ISO there are major colour artefacts on areas of gradient tone.
Although it does feature an exceptionally well implemented live view mode on a decent-sized tilting monitor, the Sony Alpha A330 is distinctly an entry-level model, with a limited range of features and options. While those upgrading from a compact camera will feel right at home, more experienced photographers will find its limitations restrictive. Build quality is adequate and the camera looks good, but the new body design is awkward to use.