By the way, it also seems like Gliwice is a kind of high-tech hotbed
No, it's just too small statistical sample to be very reliable. When you look at the biggest job portal: pracuj.pl/praca/programista:
Then mazowieckie with Warsaw is 1st, then dolnośląskie with Wrocław 2nd. małopolskie with Kraków 3rd. 4th is śląskie with Gliwice - the part of Katowice metropolitan area. Quite bad ratio, considering, that it's around 3mln people (en.wikipedia.org/wiki/Katowice_urban_area )
It reflects what I've heard that Warsaw is the best for jobs, then Wrocław and 3rd Kraków. ( Although this little old report shows higher earnings in Kraków -
When comparing these cities look at outdoor activities too. Kraków is close too high rocky mountains, Wrocław is not far away from mountains, but they're not rocky there. Warsaw is away from any sea or mountains. In summer people go from Warsaw to Mazurian lakes. (if you like mosquitos). From Wrocław you can go for a weekend to Prague (5h with a cheap bus). From Kraków it's 7h to Vienna with not so cheap train. Warsaw has 5:30 with not so cheap train to Berlin, 3h cheap train to Kraków and if they finish renovation of rail line in 2016 - 3h expensive train to Baltic Sea:
I was curious how it looks in other job portals. So here is popular free one: gumtree.pl/fp-programisci-informatyka-i-internet/c9005
Kujawsko - pomorskie (10)
Here Kraków has more adds than Wrocław. Śląskie is even worse than in previous website.
1 more thought. You entitled this topic "Quality of life", so it's important to add that Kraków has one of the highest air pollution in Europe during winter.