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Just starting on this, not for merging yet, but feedback welcome.
Tell me again why you didn't choose "Metric"?  

Would this be correct? Say I have the following line:
```
cpu.load host=servera 1418065450 5
```

`cpu.load` is a "measurement". `cpu.load host=servera` is a "series". And the entire line is a "datum"? "Metric"? "Point"? What do we prefer? All the data for `cpu.load` is called what? I am guessing that all the data for `cpu.load host=servera` is caled "series data".