No issues in SE Scotland
This certainly was not UK wide in my experience. I've got a monitored 24x7 UMTS broadband connection on 3, and there were no observed blips on this service today. I suspect the geographic impact of this outage may have been far more limited, than the articles made out.
I still maintain Three is one of the best mobile carriers in the UK, especially for data. I run a business which relies on me being able to access fast internet pretty much anywhere. I used to run dual-carriers for resilience (Three as primary, one of the others as secondary, depending on coverage), but experience showed ThreeUK to be very reliable. I've now dropped the redundant carrier, as it was a waste of money and more often than not, the redundant link on the alternate carrier would fail anyway! Oh the irony!