Has anyone used TheFork.com?
We used it recently for a booking and found it disappointing, especially for ensuring a reliable reservation (your fear) and also for getting reliable information about featured restaurants in its review section.
Though our reservation had been confirmed by thefork.com (lafourchette), we received two additional emails and one voice message from the restaurant (Helene Darroze) threatening cancellation if we didn't call to confirm.
Following the meal, we received an invitation to complete a 7-question survey but were also told that they don't publish all survey results. Upon looking more closely at the site, it appeared they actually publish only a very small percentage of reviews received.
The difference between thefork and open table is pretty striking in nearly every respect. One explanation is that thefork.com is an entity backed and run by the restaurant industry in France and Spain. It's not an independent company like OpenTable. Nancy S. and mangeur are both correct; definitely better to confirm by phone. Of course, that also begs the question of why bother with thefork.com at all (unless forced to by the restaurant).