Think it depends on all manner of things, sure the job market opening back up and people leaving is a major factor for employers who have taken people on with their own interests first, employing them at the lowest possible rates etc, but i would think that employers who had done this probably had one eye on the horizon waiting for the reccesion to end; ie they knew it would happen but wanted to milk it for all it was worth before things started to get better, as im sure we are all aware some companies profited from the fact people were in some cases willing to take anything that was going.
The type of company you mentioned in the blog; the factory? I dont see them having any problems replacing any staff who should choose to leave to be honest. There is always an abundant workforce for these type of businesses/industries, all that will happen is that Joe A the Engineer will find a job back in Engineering and be replaced by Joe B who is one of the current unskilled unemployed, sure the skillset will be different, but it wont matter in that type of industry. They wont have to raise their wages as those unemployed at the moment will be in some cases grateful to be back in employment.
In our industry the mention of the Reccesion being over has somewhat turned the tables; where we were forced to take what rate we were offered as 'it was the only thing going', we now find ourselves being able to go back to the previous way of things by asking for what we want, what with the rumoured work in Aberdeen/Dubai/Abu Dhabi etc. This could very well leave my current employer short staffed, but we are in an industry where the employer would simply raise their rate to retain. Like i said, theyve milked it for what it was worth when they could and in return people in my line of work will now return the favour as it were.
So in short, i think the news of recovery will only really affect things higher up the chain, but even then i think the result will only be offers of rate increases and new contracts based on the rates before the recession 'happened'.
Sorry if this is a little disjointed, its rushed as im typing with one eye looking over my shoulder!