By Luke Smith Follow @LukeSmithF1 on Twitter

Mercedes' announcement that it would be snapping up its option on a Formula E entry and joining the electric revolution in 2019 caused quite a stir in motorsport circles when the news dropped on Monday night.

To have one of the world's biggest manufacturers and, perhaps more poignantly, one of the most dominant forces in global motorsport this decade joining up with Formula E speaks volumes about the series. The fact that Mercedes will be shutting down its long-running DTM programme in order to focus on its electric racing interests does as well.

Like it or not, Formula E is the future of motorsport. It's up to manufacturers to jump on board or get left behind.

The rate at which Formula E has accelerated is startling. From what was chiefly a privateer grid back in season one, season six will currently feature the likes of Mercedes, BMW, Audi, Renault, Jaguar, DS (Citroen) and Mahindra, as well as EV specialists NextEV, Venturi and Faraday Future. Expect more names to be added to that list soon.

It is a raft of manufacturers that is the envy of most other series worldwide. Formula 1 only has four to its name - Mercedes, Ferrari, Renault and Honda - and is currently working on plans for its post-2020 regulations in a bid to lure more to the table. Right now, electric vehicles are the primary focus for manufacturers in their road car divisions, making Formula E the most road-relevant championship out there. At a fraction of the price of an F1 programme, it makes a huge amount of sense.

The biggest criticism laid at Mercedes following the announcement was that Formula E wasn't yet big enough or interesting enough to jump on-board with.

From an entertainment standpoint, there is some merit to that claim. The cars aren't exactly speed demons, nor do they offer the same kind of sensory delights that other championships do by way of the sound or smell of racing. The races themselves have often been more notable for the on-track incidents than their racing quality, proof coming in that one of the series' most iconic moments has been the flying crash that Nick Heidfeld suffered in its inaugural race in Beijing three years ago.

But the races often descend into strategic battles that really test the mental muscle of drivers out on-track. Take Lucas di Grassi's victory in Mexico City earlier this year. Despite nearly falling a lap down at one point, he was able to complete a mammoth second stint, exceeding his energy targets by miles to hold on and claim a remarkable win. In F1 terms, it was a driver extending his tyres way beyond their expected life despite his rivals having much fresher rubber just behind, hounding him for a pass.

There is entertainment there. It's a matter of tuning in, giving it a chance and really understanding the racing. If you watch motorsport purely for the sound and smell of racing, then Formula E is not for you. If you want to watch a real sporting battle play out, then it is there to see.

Formula E does face some big challenges in the near future, though, with the arrival of manufacturers only adding fuel to the fire.

Cost control is perhaps the biggest challenge any series faces when it adds a number of manufacturers to the fray. No series has properly got on top of costs, and Formula E is well aware of the challenge that is to come. Put the likes of Mercedes, BMW, Audi and co. at the same table, tell them to beat each other, and it's inevitable that costs will spiral. Formula E's road map has been thought out well in order to try and curb this, but more plans need to be known beyond season five.

Lots of manufacturers mean there will inevitably be some losers - and losing is not something companies of this stature are interesting in doing, particularly if it comes at a heavy price. A mass exodus of manufacturers down the line would not look good.

But electric is such a crucial part of the automotive industry's future, it's hard to foresee a situation where there will be a shortage of manufacturers wanting to join the grid. With Mercedes' arrival, we're up to 11 for season six, leaving one free grid slot. Said grid slot has a EUR25 million bounty on it, meaning any commitment must be pretty serious. The only other option would be buying an existing privateer team, but the only one without manufacturer ties right now is Techeetah.

Besides those already firmed up to join the Formula E family, Porsche is known to be considering an entry, while Volvo has been linked for a long time and recently announced that all of its cars will be electric in some regard from 2019. Nissan has also been floating about, and even Ferrari president Sergio Marchionne has expressed an interest, perhaps for a Fiat-Chrysler brand in the future.

Formula E's on-track product should only improve as it grows. From season five, there will no longer be car swaps, with the battery technology set to be sophisticated enough to allow the entire race to be completed on a single charge. There will be a need to introduce some kind of in-race pit stop, with one idea raised in the technical working group being a 'charge up' at pit stops: the longer you stay in the pits, the more available energy you have to use, trading off pace and track position a bit like fuel stops.

Technology is the focus for Formula E, and is the chief reason for manufacturers to join the fray. As a marketing exercise, it certainly looks good for an electric range of cars to be linked to a racing programme. But just as F1 and Le Mans have been the playgrounds for new technology that dripped down to road cars in the past, Formula E is the place to be now.

NextEV has already been putting this into action. Its racing team, set up in the first season, has been key to helping the development of its new supercar, the NIO EP9. It holds the track record at the Nurburgring for an electric car, set back in May, and even briefly held the overall record at the Nordschleife. That is Formula E's technology in action. And to have bragging rights like that is what every single manufacturer on the planet wants.

So say what you will about Formula E, but it is unquestionably the one championship worldwide that every manufacturer has some kind of interest in right now. It is heading down a path with some daunting challenges, but that is the flip side of growth and success - it's no bad thing.

Manufacturers don't go racing just to go racing. There must be a reason behind it, be it to push technology or to act as a marketing tool. Formula E ticks both of those boxes in a big, big way.

Formula E is no fad. With so many major manufacturers on-board, it is here to stay and flourish. Is it different? Yes. But that's why manufacturers like it. And why it is the future of motorsport.