Upgraded my internet speed

I've been using Eircom as my ISP for ten years and during that time the service has been very reliable.
The download speed started at 1 Mbps and slowly made it's way up to 8 Mbps over the first 8-9 years.
Recently, a further upgrade was announced to 12 Mbps. However, my internet suddenly became very unreliable and, at times, even unusable.
Turns out that the line into our house wasn't able to handle the higher speed and we had to go back to the 8 Mbps to regain signal reliability which, of course, if very much more valuable than the download speed.

However, as it now seemed that we were stuck at 8 Mbps for the foreseeable future, perhaps it was time to consider changing ISP.
Now just recently a fibre-optic-based system was installed by UPC in our area offering up to 100 Mbps so we went for that and have been using it for almost a week.
Conclusion?
For general browsing, email-sending, youtube video watching, essentially no noticeable difference is observed.
Even playing WoW, I'm told, the higher speed and reduced latencies makes no real difference.
Downloading can be a lot faster, of course, but I've yet to see anything approaching 100 Mbps (12 MB/s) download.
The best I've seen so far is 4.5 MB/s (= 36 Mbps) when downloading the Ubuntu 11.10 iso.
Of course, you can only download as the speed at which your file is being uploaded. My guess is there are few servers uploading stuff that fast right now.

Using UPC's download, upload speed test meter, we typically get around 70-85 Mbps down on desktop and laptop machines (ethernet) but this falls to 40-50 Mbps with wifi.
My iPad 1 gives me 15-25 Mpbs down using the speedtest.net app which on my iPod Touch 3G I get 7-12 Mbps down.
Upload speeds are remarkably more consistent and rarely, if ever, vary outside the range 6-11 Mbps even on the iPod Touch on which I've measured (again using speedtest.net app) 10.5 Mbps up.