In the compact camera range, with the latest cameras,these days, there are mostly the same, all have pro's and con's, and produce very good images, under general conditions. Lots of people have good and bad exp with the same brand/model of compact digitals.
You could read articles all day long, and still not get the "best" one for your sister.
First thing is suggest, unless shes on a world trip leaving tomorrow; find more about what she wants to use it for. look at every day and styles she likes, then look for those features. Knowing what types of pics she wants to take, you can choose a better fit, in getting a compact, that would suit her needs.
My choice, would ensure its got auto modes, and manual adjustments.
I choose Casio Exslim EV8, for one main reason 8x optical zoom, on 10mp camera. even over 12mp models available.
Dont expect the same results from compact camera, compaired to high end DSLR. That dosent mean you cant her great photos's but you need to understand what the portable camera is able to do.
The most important advice i would give is really learn what the strenghs and weakness are on the camera she buys, take all sorts of shots, lots and lots under every condition. you can adapt how you shoot if you know how a compact will behave under difficult conditions.
I bought Nikon Coolpix to start out with and I think it's ok. All of the photography in my gallery is taken with it. It's a good compact camera but some editing in Photoshop is required to get better results.
Sony Cybershot, any of the higher end models with a wide-angle lens but NOT one of the T2 or ones with a touch screen... the focus is the camera specifics, not the fancy interface, and personally I think buttons work much better.
I cannot comment on pic quality, but if she is even the slighten bit clumsy or careless, look into the new Olympus ones... They are shock resistant up to 6 feet and Water resistant up to 10 or 15 feet now...
I learned taking pictures on Canon PowerShot A630 and I find it the best camera from cheap compacts so far. Except the fact it is good for learning, for taking pictures everywhere it`s perfect for macro. Go to my gallery and see pictures taken with it at the total beginning on my way with photos, as some example what it can do when person is learning. I hope it helps
I know the Panasonic Lumix range is pretty damn good. Most can record in HD, which is always a good thing, and most are about 9-12MPx. They also use Leica lenses which is also a good thing. I'd go with Lumix, Sony's Cyber-shot [they're pretty much the same, except they use Carl Zeiss lenses ], or Canon, cos, well most Canon camera's rock!
I've been using one of the Nikon Coolpix one's. It's been really good for me. I'm pretty sure all the images in my gallery were taken with it, 'cause I've only just bought my dslr, so you can check them out if you want. It's a pretty solid camera!
Canon IXUS 870 is what I have (besides my DSLR of course) and I really like it - it's nice and easy to bring with you when I don't want to drag along the big one and it takes pretty good pictures. This have been taken with it (no post processing besides resizing): [link] The main feature about this specific camera is that it's capable of taking wideangle pictures which is quite useful in a compact.