The Canon Powershot SX30 looks totally similar to the Canon Powershot S3Is (12x and 6mp) I have had for 4 years - except it has more of everything.
After skimmming through a couple of reviews I can make a few comments based on my experiences with the S3Is ... and my prejudices.
SIZE: Cnet says the SX30 is big and clunky. No problem - I like a camera that looks and can be gripped like a 'real' camera. Advantage is that is smaller than the SLD's and I carry it on top of other junk in my general purpose shoulder bag.
LCD: It is small and not that bright. But 99% of the time I use the view finder on a camera anyway. The fact that you can change the vari-angle LCD to many positions is a real plus in some unusual situations that I will not go into.
ZOOM: I do not care what others say but I reckon that even with a good auto-stabiliser anything over 10x zoom needs a tripod. Most photos I take in China do not need more than 12x zoom because if you are any further away something is going to get get in the way --- including a lot of polluted and dust-laden air.I reckon that you can reckon on getting camera shake sometimes ... the auto-stabiliser is good but over 10x the shot becomes problematic
MACRO: It is really quite good - use it a lot
ISO: This is a real problem - anything over 400 on a Canon seems to produce a lot of noise. From what I have read the SX30 has the same problem. It is a very real problem at times in China.
AUTO FOCUS: Generally ok - but sometimes, when ripping off a shot, it gets confused
BATTERY: I can use rechargeable 4 x AA batteries on mine and I am real happy with that. I can take heaps of photos (700+ with 2500's ... I have done that on a Sports Day ). If needed (so far, never) I can change batteries and keep shooting. I think the dedicated battery of the SX30 will be a limitation.
VIDEO: I did not buy the camera for video (better to get video camera for that) but to me the video function is great. Takes real good clear video with great sound. Got a real surprise
PHOTOS: This is the real problem area with a Canon. While the photos are generally ok they produce soft images with the odd minor technical problem. Colour is thereabouts but it is not easy to get the skin tones exactly and consistently right for Chinese people (in my opinion).
I read once that Canon persists with a not-so-great programme for JPEG conversion and this is the source of the problem. Video conversion, on the other hand, uses a good programme so that accounts for the difference.
OVERALL: If I wanted real sharp, clear and accurate photos I would go back to Asahi Pentax. I bought the Canon because it was totally multi-purpose and, by and large, I am happy with the way it has performed.
While I would like to have sharper photos Chinese girls find them scary (show every blemish etc) so the softer look is ok for portraits . . . so in a way that is a plus.