• Supply chain setbacks are slowing the delivery of many popular gift items and making it harder for retailers to manage inventory during the busy shopping season.
• Some stores may end up with more holiday merchandise than they need, and that means even better discounts could follow.

By nearly all accounts, this Black Friday could be bigger than ever.

Nearly 2 million more people are expected to shop from Thanksgiving Day through Cyber Monday (Nov. 29) this year compared to last year, according to the National Retail Federation.

"We're expecting another record-breaking holiday season, and Thanksgiving weekend will play a major role," said NRF President and CEO Matthew Shay, in a statement. 

But just because it could be a record-breaking Black Friday, it doesn't mean the deals will be bigger.

In fact, sales on some items won't be as good as they've been in previous years.

More from Personal Finance:
How to shop early and still get the best deals
Thanksgiving dinner is more expensive this year
How to limit the bite inflation is taking from your budget

For example, video game consoles are in high demand and low supply, which means the markdowns will also be lower, if you can buy one at all, according to Julie Ramhold, a consumer analyst with DealNews.com.

"You'll want to purchase that PlayStation 5 or Xbox Series X or S as soon as you can get your hands on one," she said. "They've been hard to keep in stock for the last year, so they're selling out in the blink of an eye.

"If you risk waiting until Black Friday, you may end up missing out entirely," Ramhold added.

Supply chain setbacks are slowing the delivery of many popular gift items and making it harder for retailers to manage inventory during the busy shopping season.

That could result in some items arriving in stores only after the holiday buzz dies down, according to Casey Runyan, managing editor at Brad's Deals, an online discount marketplace, which means there could be even better discounts after Black Friday has come and gone.

"At some point, their delayed orders will arrive and they'll have far more than they need," Runyan said. "This is where we may see great late deals on marquis items like TVs, brand-name kitchen electronics and toys."

Runyan recommends buying the gifts you need now but holding on to the receipts so you can get an adjustment if the price falls in December.

This year, many retailers are offering some added insurance for early shoppers (although exclusions apply).

At Target, for example, you can request a price match if the price goes lower on or before Dec. 24; however, the offer only applies to select competitors and the item must still be in stock.

Walmart and Best Buy have similar policies, but Best Buy specifically excludes competitors' special Black Friday pricing starting the Friday before Thanksgiving Day through the Monday after Thanksgiving.

"If you want to ensure you don't have a panicked last-minute gift hunt, shop early and go ahead and lock it down but know the return policy in case you find it at a lower price later on," Runyan advised.

And, as always, there are some categories that are never worth buying in November, regardless of supply.

The best deals right now will be on toys and electronics, especially TVs, tablets, phones and phone accessories, as well as beauty and fall apparel.

But with other items it pays to wait, Ramhold said. Outdoor gear, winter clothing and coats, holiday decorations and gym equipment will all be cheaper come January. Interested in a Peloton bike? Those are also getting a massive price cut.

Subscribe to CNBC on YouTube.