Lamport never recommended how one should pronounce LaTeX, but a lot of people pronounce it ‘Lay TeX’ or perhaps ‘Lah TeX’ (with TeX pronounced as the program itself; see the rules for TeX). It is definitely not to be pronounced in the same way as the rubber-tree gum (which would be ‘lay teks’).
The LaTeX 2e logo is supposed to end with an ε; nevertheless, most people pronounce the name as ‘LaTeX-two-ee’.
This answer last edited: 2009-06-08
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