What I do is pick up these street compilations called La Fiesta del Reggaeton which have all the popular songs, and then I play the ones I like, or the ones that get the most reaction from Cuban dancers at Babaluu. (I think we are about 6 months behind Havana) In 2009, Gente de Zona, Yulien Oviedo and Insurrecto, El Chacal, Baby Lores all had many hits, but the group that rose to the top was Los Salvajes (los 4) with their omnipresent "Si Se Va A Formar Que Se Forma"
However, the song that blew everything else out of the water was La Charanga Habanera's "Gozando en la Habana", about the young Cuban who moved to Miami and misses life in Havana. It has become almost like a second Cuban national anthem and was still being played in Havana when i was there in November - even though it was released way earlier in the year. Without doubt the single most popular Cuban song i have ever DJ'ed.
Gozando En La Habana 5:18 La Charanga Habanera
Si Se Va A Formar Que Se Forma 3:37 Los Salvajes
La Sandunguera 4:02 Yulien Olviedo y Insurrecto
Ella Me Gusta 5:22 Paulo FG y Marvin
Me Quiedo En La Habana 4:20 Gente de Zona y Orishas
Ahora Como Te Mantienes 4:55 Los Salvajes
La Gallina 4:14 El Chacal
Washusay 4:38 Gladiator and Power Ranks
El Trio 4:29 Yulien Olviedo y Insurrecto
Homenaje al Beny 3:58 Gente de Zona
Me Gusta Te Amiguita 4:36 Los Salvajes
Volver A Su Tia 5:05 Baby Lores y Micha
The best way to keep track of the Cuban reggaeton scene is through a website out of Miami called SomosdeBarrio, which posts a constant stream of videos, mp3 downloads, interviews and gossip.
Update: Franz from PlanetTimba pointed me towards this compilation, available on iTunes, that is a pretty decent collection of current reggaeton from Cuba. (Also available in Canada)
Update #2: I forgot, Jen Paz has a great documentary out about the Cuban reggaeton scene called 'Animals of Cuban Music'
Update #3: There's an intriguing anarchy that makes it confusing for the outsider to figure out what is what. Fr'instance, the group Los Salvajes are also known as Los 4, and Los Intocables. The songs 'El Trio' by Yulien Olviedo - one of my faves - has been called in certain places 'Agua Noche' and it has had at least two versions with two different MC's William Sanchez and Blad MC.