Well, compared to OpenSSL that might be true but I wouldn't say "almost nothing": all the Mozilla apps obviously use it (Firefox, thunderbird, etc.) Additionally (according to wikipedia) it's used by Chrome, Evolution, Pidgin, OpenOffice, various Red Hat services and various Sun Java services.
Numerically maybe not so impressive but there are some pretty high-profile users there.
The main point, though, is not how many applications use it but the fact that it's (a) correctly backward compatible, and (b) guaranteed to be available on all LSB systems. LSB has a bad rep but it IS a useful baseline that's very nice to rely on, for what it contains, and virtually every serious Linux distro supports it now.