Three codes were hidden in the HTML source of the SEEKING MISTY post on the Investigate Ingress blog.

[1] 2if2vbpeo7wnced4rt2u

[2] wkbigouhguonesdlrowhriginde

[3] 5zvl26belamp69caow

Code #1

Observations

20 characters with the right amount of numbers for a valid passcode

Make a 5×4 grid

Reverse rows 1 & 3

Read going down from the upper left V

vbd42perfection227wu

Kind of a bizarre one but try to split into the passcode format.

Split into passcode format using two characters for numbers

wkb ig ou hguonesdlrow hr ig in de

The numbers are using the second and third letters of their written form

wkb84 hguonesdlrow 389de

Reverse the keyword part

wkb84 worlds enough 389de

Searching on Google gives a book called World Enough and Time

wkb84time389de

18 characters with the right amount of numbers for a valid passcode

Make a 3×6 grid

Read from the lower left A

aow69campbell265zv