What bumper is this?
 

http://i.imgur.com/rWMcCrIl.jpg

Is this a lip added to the standard facelift bumper or a new bumper entirely?

Looks like a factory Aerokit bumper

So it's a full bumper and not a piece that fits on?

I concur - factory aerokit 1 bumper and side skirts. The bumper is made of OEM urethane and is one piece.

Here a shot of mine, in the base model version (without center air inlet). Mine's a bit rock-chipped, and in need of a respray, but you can't say it's dirty because I just washed it. :)

That's different - look at the black one, it goes in at the centre of the splitter. Almost though!

Looks like a 2003 - 2004 standard bumper.

I think it might be a 2 piece front lip spoiler, check this one out that is in grey
1996-2001 Porsche Boxster 986 German Tuner 2pc Front Lip Spoiler (UNPAINTED)

Porsche Parts & Porsche Body Kits at the Best Prices - 997, 996 02-04, 996 99-01, 993, 911 74-89, Boxster Online SRFL

Thomas, should you buy a new front bumper cover, make sure it's polyurethane. Not sure if you know, but there's a lot of fiberglass reinforced plastic (FRP) out there and it will crack on you if touched the wrong way. Poly is a lot more expensive, but the way to go and it's how the factory parts are made.

My bumper has the feature you're talking about - it just doesn't happen to be very prominently visible in the photo from the angle it was taken from. It's more of the bottom edge of the bumper being raised higher in the middle, than it is being pushed back. So from a lower camera angle, it's more noticeable.

If you google image search boxster aerokit 1 you'll see other examples that show it more clearly. But there aren't a whole lot of pics of it out there - it seems somewhat exclusive and rare. :)

http://986forum.com/forums/show-tell-gallery/51800-98-aero-kit-1-a.html

http://forums.pelicanparts.com/uploa...1354042015.jpg

http://forums.pelicanparts.com/uploa...1356638892.jpg