I'm not sure this if topic is a good idea, but i figured that here you could describe an entire or a portion of a major roadways lighting. I'll start: Interstate 494 in the western suburbs, starting from the west:
Fish Lake interchange: Mixture of older and somewhat newer highmasts. I'm not certain on what bulbs are inside, but i know that some are HPS.
Fish Lake overpass [REMOVED 2015]: 5 Vintage truss-arms and one newer davit pole. A mixture of M400s and M250s (I think).
Fish Lake interchange to Carlson Pkwy. [NOT COMPLETE]: Continuous brand new GE? LED fixtures on davit poles.
Fish Lake interchange to Carlson Pkwy [BEING REMOVED CURRENTLY]: Various lighting at each interchange, but mainly M250s and M400s, and all HPS.   
Carlson Pkwy to Hwy 212 Interchange: Continuous "turnpike" lights, all HPS.
Hwy 212 Interchange to Portland Ave.: HPS highmast lighting, and one mysterious M400 that's all
alone.
Portland Ave. to Hwy 5 Interchange: Various lighting on davit poles. Unknown FCO fixtures, wihich are being changed out to LED, some turnpike lights at the 24th Ave. exit, and some non-FCO fixtures.
Hwy 5 Interchange: HPS highmast lighting.
I apologize for not knowing very many of the models. If this topic doesn't work, feel free to delete it.

Here in Illinois, most, if not all of the highway interchanges and intersections are lit by these weird 400 or 1000w post top mounted HPS flood fixtures. The more down south by Edwardsville is a bunch of holophane vector fixtures. On regular roads, it's a mixture of ael125s and Cooper ovx in 400w MV, with fixtures replaced with 250w HPS GE m250r2s as the poles get knocked down or ballasts die from neglected maintenance. Downtown, there are lots of streets that have a mixture of 400w MV LM unistyle 400s, OV-25 Silverliners, or older m400s, which get replaced with 250w HPSyndrome as the poles fal or ballasts burn out.

I actually drove through Illinois this winter break. Do you know what are those funky lights on Interstate 57 are called? They look somewhat like an OV-20 and are mounted like a turnpike light. They were located at most rest areas and a few highway interchanges, and some were also mounted on highmast poles.

US281 in San Antonio, Texas  loaded with OVW,  same for I10/ hwy90 interchange in down town OVW on double guy poles. i35 north have mix of HPS installs
From L150 to GE m400/  and mix of other stuff.
Loop 410 on north side of town, by North star mall area
Got those hocky puck looking HPS on square poles.
It was MV install with mix of poles and double guys
It was last install of mercury lighting that got killed
By freeway expansion project back in 2004/2005

I'm not sure this if topic is a good idea, but i figured that here you could describe an entire or a portion of a major roadways lighting. I'll start: Interstate 494 in the western suburbs, starting from the west:
Fish Lake interchange: Mixture of older and somewhat newer highmasts. I'm not certain on what bulbs are inside, but i know that some are HPS.
Fish Lake overpass [REMOVED 2015]: 5 Vintage truss-arms and one newer davit pole. A mixture of M400s and M250s (I think).
Fish Lake interchange to Carlson Pkwy. [NOT COMPLETE]: Continuous brand new GE? LED fixtures on davit poles.
Fish Lake interchange to Carlson Pkwy [BEING REMOVED CURRENTLY]: Various lighting at each interchange, but mainly M250s and M400s, and all HPS.   
Carlson Pkwy to Hwy 212 Interchange: Continuous "turnpike" lights, all HPS.
Hwy 212 Interchange to Portland Ave.: HPS highmast lighting, and one mysterious M400 that's all
alone.
Portland Ave. to Hwy 5 Interchange: Various lighting on davit poles. Unknown FCO fixtures, wihich are being changed out to LED, some turnpike lights at the 24th Ave. exit, and some non-FCO fixtures.
Hwy 5 Interchange: HPS highmast lighting.
I apologize for not knowing very many of the models. If this topic doesn't work, feel free to delete it.

Fish Lake: I'm starting to see sodium lamps appear, normally with a couple of fixtures per pole converted and the rest left dark. This area used to be very bright, 1000 metal halide lamps were installed in the same fixtures that used to hold mercury vapor.

Any LEDs you see are not GE. Current Mn/DOT approved products are American Electric ATBM (most of the ones I've seen going up in the last few months are these) and Cooper Navion NVN. Previously some other American Electric and Cooper fixtures, as well as some by Philips and LED Roadway were approved (but none by GE), but these were yanked for some reason. They're having bad luck with whatever was installed as a test on the Minnesota River Bridge; a while ago a power surge blew out half of the power supplies, now about 3/4 of them are out again.

UPDATE: I drove past the Fish Lake interchange today and noticed brand new LED highmasts waiting to be installed. I am very interested to see how these turn out, and will post an update when I have more information.

Here in Colorado it's pretty much all HPS, no MV or MH for state routes, though some municipalities use MH and a few still have a couple of MVs.  CDOT & XCEL Energy have been experimenting with LEDs up in the high country and are satisfied enough that XCEL is going to begin a 5-10 year statewide conversion program this year to upgrade/change out the cobra heads to LED cobra heads.  They are not yet sure what they are going to do with the residential pole fixtures.  In talking with my contact at XCEL who is over the street lighting project, she tells me that the color is going to be between 3500-4100K.  Thank goodness it won't be the horrible crispy white color.   

UPDATE: I drove past the Fish Lake interchange today and noticed brand new LED highmasts waiting to be installed. I am very interested to see how these turn out, and will post an update when I have more information.

I emailed the Mn/DOT lighting engineer that's in charge of new installations. He reported 1) Yes there are new lights going up at Fish Lake Interchange, and 2) They will be HPS, not LED, as Mn/DOT has not approved a high mast LED product (although there's a few being tested out on I-494 near the Wakota Bridge).

Ah okay. Did the engineer by any chance tell you why the new highmasts are going up? I had figured they might be retrofitted to LED, or they might be removed altogether. In any case, it'll be nice to see a new HPS installation.

I didn't ask, but it's the oldest installation on the freeway system and was identified in a study a few years ago as needing replacement. The installation in general is at EOL- old mercury vapor fixtures, old wiring, old foundations.

Nice to hear that they are going to do something other than LED for once...

Update: As of 7:00 PM yesterday, most of the new highmasts are up, and most of the old ones are down.