Jet Li isn't all special effects, given the number of Wushu competitions he has won, even being declared a national treasure by the People's Republic of China.
What is interesting is that Jet Li has admitted that people that do boxing would be hard to defeat given how quickly they can dodge when you are using a traditional martial arts style like the one he practices. Although a Wushu champion, he actually comes from a long line of martial artists.
The boxing point is interesting as Bruce Lee practiced not only martial arts, but boxing as well.
Also, given that Jet Li is a Buddhist and Bruce Lee believed more in solving an argument through talking (his opponents picked the fights) this would probably end up quite a boring fight as both of them would be smart enough not to come to blows over something as trivial as who was better. The have both expressed respect for different styles of combat and hardly seem the kind of people to go around picking fights.
Both of the have extensive filmographies with quite a few martial arts movies, yet Bruce Lee managed to die mysteriously at the age of 32 and Jet Li is currently 44, which could show that Jet Li is luckier or blessed more than Bruce Lee. A curse seems to formed around the Lee family, as Bruce's son Brandon was shot dead whilst filming The Crow.
While interesting, I do find it all to be a moot point as my money is on Tony Jaa.
"The blood-dimmed tide is loosed, and everywhere
The ceremony of innocence is drowned;" - William Butler Yeats
B9 5E 43 72 1F D8 F5 1E 1A 9C 7E AB 04 20 E9 DC - This is my 128-bit integer, don't get any ideas about stealing it.