At first, garages seemed more of an afterthought, hidden behind the home or built as a separate entity. This garage seems more like a shed than a garage, and it doesn't even match the house's style, as the roof is facing a completely different way.
This garage is still detached, but at least has the same color and gable as the rest of the house.

I don't know what to call this... semi-attached garage? Not sure how well that covered walkway protects these homeowners from blowing snow/rain that comes at you sideways.
Finally, an attached garage! While this house is the same style as the one above it, I would guess the garage wasn't originally attached. However, the hallway-mudroom was probably built later on to utilize the garage as an entrance instead of just somewhere to store junk. 

This breezeway from the garage to the main part of the house allows a nice view of the backyard from the street... These people now have three front entrances to their home. Where to ring the doorbell if you're selling candy bars?
This also seems to be another added-on mudroom, though the stairs give the side entrance a front entrance feel.
This home, (probably built between 1988-2000 like most homes in my development) appears to have a mudroom. However, it is nothing more than a walk through door into the garage, indicating this may be a 2.5 car garage and a fraud?

Jackson briefly discussed the three-car garage. I agree that it makes the home look larger and gives the indication of more wealth. A few of these homes do have more than two cars, yet often they are parked in the driveway because the three-car garage has become a basement addition (meaning that it stores a lot of stuff, leaving no room for cars!).




Another trend seems to be the attempt to hide the garage and make the door not visible from the street view of the home. Maybe it is so the house appears to be larger than it really is; a number of the homes pictured above even put drapes/shades in the garage windows so it looks like the rest of the house. Most of the homes pull off the look from a dead-on view, but the last two houses pictured failed, as they are actually on a corner lot. Everyone can clearly see their "front" facade is a fake as the garage is visible from the side street. 
At the complete opposite end of the spectrum, some homes seem to feature the garage as an element of the home. By building on top of the garage, as is so vital in the raised-ranch style, homeowners can utilize upward space on a narrow lot (much like skyscraper developers).
Other home builders seem to push the garage way further out in front than the rest of the home. It must also be to maximize square footage by building back into the lot, as in the ranch pictured above. The second home's garage seems to be wider than the front of the home itself. (Dolores Hayden calls these homes "snout houses", which I think is very appropo.)



These two homes from my childhood street, Jane Lane (in a neighborhood of girls' names, my street was the only one that rhymed) show the original porches, with the second being enclosed (also known as the house which always gave out apples for trick or treat on beggars' night, as 




























