In the late 1980s and early 1990s, the McLaren-Honda partnership was one of the most successful in all of motorsports. Their five year partnership netted four world championships and a second. And starting in 2015, they want to recapture that magic once again.
In an announcement that everyone saw coming for months, Honda has confirmed that they will supply McLaren with new turbo engines in 2015. That means that 2014 will be McLaren's last year with Mercedes power, which has been behind them since 1995.
It sounds like a really great reunion, but there are a few interesting points to make note of. First, the 1988 to 1992 run that Honda had with McLaren was with Ayrton Senna and Alain Prost at the wheel of the cars, two of the most talented and celebrated drivers to ever compete in Formula One. Jenson Button and Sergio Perez are good, but they aren't the dominant force that Senna/Prost were.
Secondly, in a statement, Jenson Button called Honda "one of the most experienced and accomplished builders of turbocharged engines anywhere in the world." He surely doesn't mean road cars, because as far as I can tell they've only had three turbo engines come out of the factory: A 1989 V6 in the Legend, the Honda City Turbo, and the turbo four in the last RDX.
In F1, the Honda turbos ran from 1983 until 1988, where they were very successful in supplying Williams, Lotus, Tyrrell, and finally, McLaren. They also had some crazy good turbo engines in Champ Car in the 1990s and 2000s.
Jenson must have some mixed feelings about this partnership, as he raced for BAR-Honda and Honda's factory team from 2003 until 2008. After the 2004 season, which was one of his best, Button tried to leave to go to Williams, but BAR forced him to stay thanks to contract issues. In 2006, Button won his first ever race in Hungary for Honda. Then, in 2007 and 2008, he had two of the worst years of his professional racing life, with cars that were basically pieces of junk.
Honda has almost always been better as an engine supplier than a full works team. If they get this engine right, then I'll expect a lot out of McLaren in 2015. If they get it wrong, expect a lot of fire and explosions in 2015.