I will not ramble on or quote anything technical as I am a photo hobbyist and just wanted the benefits of a dSLR with the benefits of a compact. There are a lot of professional reviews out there if that is what you need.
Viewfinder - is an EVF rather than optical viewfinder, which I prefer as you get a pretty good idea if things will be blown out or too dark, etc. Some people want optical but I prefer the compact style benefits an EVF offers such as shooting information such as you would normally only find on a dSLR rear screen. It automatically goes from screen to EVF when you bring it up to your face.
Video - is very good with constant auto focus (that is missing off many other dSLR's such as the Canon 550D). There is little option for manual set up for video but I tend to use it as a handy addition to a stills camera so am happy with what it does when I want video (using the video quick start button on the rear). Plus the EVF means you can video while looking through the viewfinder and getting the same view as the rear screen.
Articulated screen - is clear and turns to cover most shooting needs, not as articulated as some cameras have but pretty comprehensive for movement and the information you can view.
General controls - are good with an Auto+ setting that as well as having the normal normal auto functions includes HDR etc. The HDR/DRO button is handily placed on top alonside the main control knob that has the standard sort of advanced and beginner settings.
Size - is just right without the bulk of a 'normal' dSLR but with sufficient weight to keep it steady. I have a Sony 18-250 lens on it and the extra weight balances is nicely. With the small kit lens on it is a comaparable size/weight to a number of bridge cameras.
Photo quality - is almost as high as the 550D I used to have (although I am not a pixel peeper) and way higher than any compact or bridge camera especially in low light/high ISO.
GPS - is not particualry fast but it will use the last acquired position so if you are not moving far or are moving inside you can still geotag even if the position may be slightly off.
Battery power - is not brilliant so I bought 2 extra non Sony batteries on Amazon for about £13 each Ex-Pro Sony NP-FW50, NPFW50 High Power Plus+ - 2 Year Warranty Replacment Sony Lithium Li-on Digital Camera Battery for Sony NEX-3, NEX3, NEX-5, NEX5, Sony Alpha A-33, A33, A-55, A55
, there are cheaper ones but these seem to last about the same as the Sony one.
Vs bridge and compact - I still carry a small pocket compact but do try to carry the A55 as much as possible. Unless you are buying a bridge camera for some huge zoom function I would definitely recommend an A33 or A55 as the overall quality and versatility in low light and/or indoors is way ahead of any bridge camera. Buy a cheap mid or long zoom compact for good light and an A33/A55 for other photography (even if you only get the short kit lens) as the difference in anything other than good daylight is very noticable.
General comments - the best camera purchase I have ever made, although I appreciate the purist may not like it compared to a normal dSLR. The quality and convenience give me the perfect combination of dSLR quality with some of a compact/bridge benefits. I highly recommend it and am happy I got the A55 rather than wait for some improved (and more expensive?) A77 some time next year.