As The Artist Formerly Known As Prince might have said, "It's a sign o' the times..."

Visitors to this year's IPTV World Forum event in London, which opens its doors Wednesday, March 25, will find some of the sector's biggest names missing from the show floor, though not completely absent from the proceedings.

That Thomson S.A. (NYSE: TMS; Euronext Paris: 18453) doesn't have a stand might not come as too great a shock. The company, which supplies service providers with set-top boxes, gateways, video servers, and IPTV middleware, is undergoing a revamp and is more focused on saving money than spending it at present. (See Thomson Revamps, Tackles Debts, Thomson Ships Home Hubs, and Thomson, Ericsson Bag IPTV Deals.)

It hasn't abandoned the show, though. Thomson is still a sponsor and a presenter, and is set to announce a new SmartVision server focused on increasing service delivery quality during the three-day event.

The major surprise, though, is the absence of Microsoft Corp. (Nasdaq: MSFT) from the show floor, though it has a prominent speaking slot and is one of the event's main sponsors.

That means you can wander the booths and check out what "Meet the Boss" (honest -- it's at Stand 41a) and a bunch of other niche applications specialists have been developing, but you can't get the latest IPTV developments from Microsoft. I was so shocked I "Twittered" it...

A spokesperson for the Microsoft Mediaroom division told Light Reading there wasn't much in the way of new developments to put on display.

Yet only a few months ago Microsoft unveiled its Anytime application at the Consumer Electronics Show in Las Vegas, and only released its Mediaroom Presentation Framework, which enables service providers to integrate IPTV and Web services, to its carrier customers earlier this year. (See Microsoft Offers Anytime TV.)

Microsoft showed off its early Presentation Framework developments at last year's London show, when it was still known by its code name, Milwaukee. (See Microsoft Preps 'Milwaukee' IPTV Upgrade.)

While Microsoft is acting a bit shy at this show, its key IPTV partner, Alcatel-Lucent (NYSE: ALU), is much more visible. AlcaLu does have a stand (one of the 120-plus companies with a show floor presence) and issued some related news today ahead of Wednesday's opening day.

Coincidentally, AlcaLu has announced its support for Microsoft's Mediaroom Presentation Framework, along with news of an interactive advertising pilot service at Spanish giant Telefónica SA (NYSE: TEF). (See AlcaLu Supports Mediaroom and Telefónica Trials Interactive Ads.)

Elsewhere at the show, middleware specialist Dreampark AB will be crowing about its latest deployment, which is at attractive Irish broadband services provider Magnet Networks Ltd. . (See Dreampark Wins Irish Deal.)

Dreampark says it is replacing the incumbent system at Magnet, though is too modest to say whose system it is ousting. A quick check shows that the unlucky niche player this time around is Industria , which had its Zignal IPTV middleware installed at Magnet.

Other IPTV World Forum news ahead of the show:

— Ray Le Maistre, International News Editor, Light Reading