Nothing much has changed in the past month looking at the usage stats but there are a few things to look at:
OU 1825
1 | Garchomp | 27.52205%
So Garchomp was #7 in february and he already made huge jumps before. Garchomp's most used set is Rocky Helmet again with 71%. Especially with Landorus-I rising in usage (#31 to #16) and with Garchomp being a better rocks setter than Landorus-T in many situations, it isn't really a surprise Landorus-T isn't #1 anymore. Other usage statistics lower on the ladder still have Landorus-T on #1 but with lower percentages than before.
As for pokemon that may drop to UU or go OU by usage
45 | Tornadus-Therian | 4.66739%
44 | Mew | 4.90389%
52 | Mandibuzz | 3.29782%
53 | Mamoswine | 3.26473%
63 | Gallade | 2.45065%
Doesn't really matter because we can use these pokemon anways, but it shows the metagame trend a bit.
Despite the huge usage of Garchomp on the 1825 stats, the other statistics show that the metagame became more bulky offensive instead of balanced. As you can see below offensive threats like Bisharp and Sand Rush Excadrill all grew in usage while pokemon often found on balanced such as Celebi, Clefable and Gliscor dropped in usage. Especially bulky offensive threats like Scizor, Manaphy and Starmie. Balanced is still the most dominant playstyle (usage stats of pokemon like Hippowdon or Tornadus-T didn't drop) but offense, and especially bulky offense, is being used more over time.
17.6% -> 21.9%
7.3% -> 11.2%
8.7% -> 11.9%
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17.1% -> 18.4%
3.9% -> 10.2%
10.3% -> 14.5%
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17.5% -> 10.4%
9.2% -> 7.4%
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Also this is what we have learnt from the 3 day Giratina-O suspect:
1 | Giratina-Origin | 76.53769%
'not overcentralizing at all'