Of the biggest six providers, BT, Sky, TalkTalk and Virgin Media appear to have adjusted their broadband promotional material and listings on comparison sites to be in line with the new ASA rules. O2 is distinctly lagging, with up to 20 Meg still listed for its unbundled services, and up to 8 Meg for its off-net products. Orange could be considered compliant on its own website, simply by avoiding mention of speeds apart from a personal estimate for your existing telephone line, but it appears to have not told third party sites what speed they should show in package descriptions.
The story is very different amongst the medium to small providers, Eclipse has opted to promote its average broadband speed of 12.3 Mbps, and at the time of publication Plusnet was still to change its pages. Of the other providers we've not seen any changes other than perhaps omitting speed, it may well be they are waiting to see what the big providers do, and follow the consensus approach.
Where providers don't mention any form of speed, they run the risk that casual shoppers who have grown weary of entering their phone number (which can lead to sales calls with some providers) will simply skip them. This is particularly the case when estimates given to consumers have such a wide variation, e.g. if I was getting 6 Mbps now, would I really want to sign up to a provider that suggested a range of 2.4 Mbps to 7.6 Mbps.
Update 10pm: We now have figures for Plusnet and their website has updated to reflect them.