By Torin Douglas BBC media correspondent

So farewell Carlton and Granada.

Farewell LWT, Yorkshire, HTV and the rest.

After 10 years of takeovers, mergers and management shakeups, the 15 separate ITV companies have finally been reduced to one, at least in England and Wales.

The two Scottish stations still have other owners, as do Ulster and Channel Television, but in practical terms - programme production, commissioning and scheduling, and advertising sales - there will now be just one big ITV company.

When two become one...

The deal is more generous to Carlton, Granada and its shareholders than anyone expected, which is why the City reacted so positively.

The new company will not have to sell off its advertising sales departments, as the advertisers and Channel 4 and Channel 5 had demanded.

It can operate, in the words of one former ITV boss, as "a proper television company" or, in Greg Dyke's oft-quoted phrase, an 800-pound gorilla, competing with the two other giants of the TV jungle, the BBC and Sky.

Carlton and Granada say a stronger ITV is good news for viewers because the new company will be more singleminded and more money can be put into programmes, delivering better quality and choice.

In fact, they acknowledge that this year's budget increase will be modest.

But a single ITV wasn't an end in itself and the merger marks the start of a new and uncertain phase for the UK's largest commercial TV network.

Some in the City aren't confident in the top team - Michael Green of Carlton who'll be chairman and Charles Allen of Granada, who'll be chief executive - often billed as "the odd couple".

Analysts blame the pair for the ITV Digital debacle, which cost shareholders a billion pounds, and find it hard to believe they can work together, foreseeing them "fighting like ferrets in a sack".

At the weekend, they challenged that notion.

Allen told the Sunday Times: "For 12 years we were paid to compete and we competed hard, but in 12 months of working together we have agreed a single budget and strategy for ITV and had a fantastic outcome from the Communications Act and the Competition Commission."

Green added: "Together we have added in excess of �2 billion to the value of Carlton and Granada."

Even so, some believe the new situation calls for a completely new management.

And there are also American predators - such as the giant Viacom group - waiting in the wings, unleashed by the Communications Act.

On the day of the announcement, Michael Green said: "A new future for ITV starts today."

The question is "in whose hands"?