After reading all the posts on this thread about 'Clamping down' on the perma-tourists, I am adding one more, to relay my most recent experience in doing the 90 day tourist visa renewal.
I am a US citizen in Buenos Aires, on a tourist visa. I have several stamps in and out of Buenos Aires and Colonia on the same day (four, five?) with various trips to the US made in between) over a one and a half year period. I have never paid the visa overstay, and have always left Argentina within the 90 days, either by going to Uruguay or the States.
I made my latest round trip about two weeks ago on Buquebus, and after reading all the negative posts on this website, I was more than a bit worried about what was going to happen.
The result? I left BA on a morning boat, and at the terminal in Colonia on the way back to BA the same day, the Argentine migraciones officer took my passport, flipped through the pages of, looked at all of the stamps in and out, gave me a nice smile and stamped my passport and gave me another three months. No raised eyebrow, no check of the calendar (I was at day 82 or something) not a single word, other then "gracias, chau!"
I'll let you know what happens in April when I go again....but as of now, I can honestly say I didn't experience anything clampdown-like, or any difference in attitude than any other migracions officer I have had to speak with in the past.
Just my two cents....