I don't believe there has been any change in the situation since the last discussions on this subject before in October 2008 here http://www.theihe.org/tsgforum/comments.php?DiscussionID=23&page=1#Item_2 and again in February 2010 http://www.theihe.org/tsgforum/comments.php?DiscussionID=197&page=1#Item_0.
It is my understanding that any temporary pedestrian facility must comply with TSRGD / Pelican-Puffin Regulations as appropriate either as a temporary junction pedestrian facility or as a stand-alone crossing facility. As such it must use signal heads to Diagram 3000 & pedestrian equipment as appropriate from Diagram 4002.1-4003.7. The regulations do not permit the use of the portable signal head Diagram 3000.1 in combination with any pedestrian signal heads.
There is a draft TSRGD amendment floating around to change this which was subject to consultation at the end of last year but I've not heard when it will eventually be bought before parliament.
We thought that the situation was as bvefore - ie that the portable heads didn't comply, but obviously finding confirmation that nothing has changed is always harder than finding new info!
Contact Suku Phull at DfT for the definitive answer, but I think Mark's summary is still correct - the DfT have a few other things to worry about at the moment than getting the TSRGD revisions out.
In Derby we are using them quite regularly despite my own reservations. Our Network Management team say that in terms of risk they are better than the option of not using them. Usually they don't bother with any markings either just "When red light shows" boards.
Which brings me back to a comment I've made before on here. Who checks that Highway Authorities are complying with the regulations etc. I suspect unless there's an accident which brings about a specific check then you could do what you wanted for years.
Whilst I still have both feet in the "Its not prescribed don't use it" camp (although they are becoming itchy) I think Ian raises a fair point here. We've moved into a world where many things are being challeneged, leading to arguments having to be strengthened, or we have to become more open minded
The question I would ask here then is has there been a legal test case of any form or kind following an accident at a portable crossing. If a formal documented risk assessment existed that demonstated beyond rerasonable doubt all options had been considered and a portable crossing posed the least risk to pedestrians, then is that sufficient to proceed ? Its worth also bearing in mind that in court whilst the reasons for using a portable crossing could be critisiced, a clever lawyer could also critisize for not using a product that is readily available.