As discussed earlier, there's a big difference between announced "Subscribers" and real players.
But what a lot of people want to know is how many real players are there playing RIFT right now?
According to Trion (Source) they had a grand total of 58 North American and 41 European servers prepared for launch.
Trion also pleasantly provides Shard Status information. It's very limited (just like Blizzard's - you don't want to reveal too much information), but it does let you know how many people are waiting in queue.
Right now, the Dayblind shard is FULL with 112 people waiting.
I counted the total number of players on Dayblind (very tedious and time consuming by the way), and it came out to around 1900 players (Defiant and Guardian combined). Let's say for argument's sake that their servers are maxed at 2,000 total players (a very reasonable estimate).
Since there are 99 total servers, that means that they can support AT MOST 198,000 real players.
Keep in mind that these are peak concurrent logins and it was the busiest period (9PM-11PM showed about the same numbers, then tapered off) for NA. Many servers are still showing Low and Medium (probably 1200-1500) populations too.
(Note: If you play RIFT, pull some numbers from other servers during peak hours and leave a comment here - e.g. total players on both sides. I suspect all of the servers have the same max. number though. Remember that these are peak concurrent logins at a certain time of day. Other players login during different schedules.)
There are also other factors at play, some players haven't started playing yet, and they might increase the player capacity on each shard at a later date.
Take this information for what you will, but I wouldn't be surprised if real players were somewhere between 100,000 and 150,000 total right now (based on average player activity cycle and that over 50% of the shards were at half capacity.) If there were "1 million subscriptions" as promoted by gaming news sites, there should have been at least 600,000 simultaneous users logged in during peak hours.
Even if all of the shards were completely full, that would probably amount to 250,000 to 275,000 total players max during peak hours. That would mean less than 425,000 total players who would be logging in throughout the entire day. A far cry from the "1 million subscriptions" that gaming news sites are mistakenly reporting anyways. =]