Not a big Satch fan...
And I'm definitely not a Coldplay fan... but I'm sat next to one at the moment (Mrs Andyr says hi)...
We followed the youtube link and... we both think Coldplay'll get done, or they'll settle out of court...
I personally don't think any established artist nowadays would deliberately plagiarise - they'd be absolutely stupid to do so, it's just not worth the effort of recording and marketing the thing. But it is so easy to come up with something that you think's original, especially when it's catchy, and then someone turns round and goes "hey, it's just like so-and-so..." which is not what you intended at all, but you know you've heard "so-and-so", though you don't listen to it regularly, and on reflection you do seem to be subconsciously quoting it... so you end up binning the new song. I suspect that's what's happened here but no-one in the Coldplay camp spotted it.
I feel for both sides - when I read this yesterday, not able to listen to it (or know either tune), I thought "Satch is being daft", but having heard it, I know exactly how he must have felt when he heard it - he had to do something (maybe he did, and Coldplay's publishers/etc said "f*ck off" and that's why it's gone this far!!).
I also feel for Coldplay. Unless they nicked it deliberately (which I doubt) they'll be feeling a bit hard done by. But assuming they're creative people who are used to writing songs - they'll know it's possible to accidentally plagiarise.
All in all, I think both sides will seek an agreement of some sort. Unless either camp is feeling bloody-minded I reckon they'll probably cut a deal to get it done as quickly/quietly as possible.
:D