Just like the iPhone LCD leak back in March, SmartPhone Medic got their hands on another piece of next-gen iPhonehardware. This time they've posted a video of the middle plate assembly for the upcoming iPhone. SmartPhone Medic notes that the part looks identical to the one in the prototype iPhone Gizmodo bought, and from what I can see it looks like they're right. The visible black seams in the case are still there (yuck), and it appears that the SIM card slot has moved from the top of the case to the side, similar to the layout on the iPad. The metal plate fits perfectly into the iPhone front face and LCD assembly that SmartPhone Medic showed off in March, so it looks like that leaked part was the real thing.
Other than the "guts" of the iPhone (which won't see the light of day again until its official release), the only part SmartPhone Medic has yet to show off is the iPhone's rear casing. There's still no definitive word on what the material of that rear case is -- some have said glass, while others are saying it might be some type of ceramic. We should know the answer to that question very soon: WWDC starts on June 7, and almost everyone expects the next-gen iPhone to have its (official) debut at the keynote.