Can anyone confirm for me (preferably based on personal experience) whether first class Eurostar seats ending in "1" and "2" are the single seats facing each other? Thanks!!

On my seating diagram for each car it appears seats ending in 1 and 5 face each other in first class - single seats facing each other with a table in between. In fact the car seat diagram, from sep 2005 shows no seats ending in 2 a'tall in first class cars. Supposedly all Eurostar train cars have the exact same make up so i don't know what to say. In standard class seats ending in 1 and 2 are located next to each other facing the same way.

Do you mean the Eurostar under the Channel? Or Eurostar trains in Italy???

I were talking about the Eurostar CHUNNEL (Channel Tunnel to U.K. folks) trains London-Paris and Brussels, not ESItalia trains. Supposedly the Eurostar name was trademarked by Fiat when they developed the ETR type high-speed trains for Italy and the Eurostar CHUNNEL trains use it too after being licensed to do so by Fiat (or the Italian Railways) - i'm not totally poistive about this so would love to be corrected if wrong.

I am specifically referring to the Eurostar Italy trains on Trenitalia(e.g., between Venice and Rome).

Well in that case i'll get out my train car diagram for ESItalia trains and it says you're right that seats ending in 1 and 2 are the isolated seats with just one seat with a window and an aisle.
In each car seats 11,12 then 21, 21, etc up to 71,72 all are these isolated seats - on some types of ES trains they indeed face each other (ETR 500 and ETR 460 - only in 460 is there a table between them, not in ETR 500 trains) So unless you're riding the older ETR 450 trains then you will be facing each other in single seats like you suspect - according to train car diagram i have dating from Nov 2004. This comes from RailEurope so they may have a more current one to consult - good luck asking them to on the phone, however.