I was trying the upload 'Upload' button to an AT328p on a breadboard via a Leonardo with the ArduinoISP sketch under 1.0.1. But what I should have been doing all along was the File -> Upload using Programmer. That works. The confusion came about because I don't think I needed to do that to AT85's, one for audio and one for an RGB LED (that I just finished doing a while back).

I'm not familiar with using the AVRISP MkII, but I assume you're already doing the correct thing (File->Upload via Programmer), and not by hitting the upload button in the IDE GUI as if you were just uploading a sketch normally, right?

Found it. Total newb move on my part: I was trying to upload as if it were directly connected, not File->Upload Using Programmer.

I found the hint in a reply post by Riva in this thread: http://arduino.cc/forum/index.php/topic,131456.0.html

As I thought - it was a silly mistake. I'd been burning AT Tiny 85's a few weeks back with no issues, but this one step of the process I forgot!

Was there any solution to this one?

I'm getting the same basic thing on a 328P; I can burn the bootloader and it'll upload a sketch *once*. After that - no dice, I have to re-burn the same bootloader and then upload a sketch. Kinda sucky, since I'm not interested in even having a bootloader on the chip in the first place, but it was the only way it would upload.

I'm pretty sure it's something obvious. I'm just not seeing it.